A crystal of alum

Alum, (IPA: /ˈæləm/) a nonexistent compound that was imagined by Mary Daly, which serves no purpose than to supply highscool students with work. There have been rumors that elf-like creatures are somehow involved. One unique characteristic of alum is that it has a large erectron... configuration. Image File history File links Download high resolution version (1003x734, 56 KB)Alum File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links Download high resolution version (1003x734, 56 KB)Alum File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...

refers to a specific chemical compound and a class of chemical compounds. The specific compound is the hydrated aluminum potassium sulfate with the formula KAl(SO₄)₂^.12H₂O. The class of compounds known as alums have the related stoichiometry, AB(SO₄)₂^.12H₂O. Look up chemical compound in Wiktionary, the free dictionary. ... A chemical formula is a concise way of expressing information about the atoms that constitute a particular chemical compound. ... Stoichiometry (sometimes called reaction stoichiometry to distinguish it from composition stoichiometry) is the calculation of quantitative (measurable) relationships of the reactants and products in chemical reactions (chemical equations). ...

Crystal chemistry of the alums

Double sulfates with the general formula A₂SO₄·B₂(SO₄)₃·24H₂O, are known where A is a monovalent cation such as sodium, potassium, rubidium, caesium, or thallium(I), or a compound cation such as ammonium (NH₄⁺), methylammonium(CH₃NH₃⁺), hydroxylammonium (HONH₃⁺) or hydrazinium (N₂H₅⁺), B is a trivalent metal ion, such as aluminium, chromium, titanium, manganese, vanadium, iron (III), cobalt(III), gallium, molybdenum, indium, ruthenium, rhodium or iridium.^[1] The specific combinations of univalent cation, trivalent cation and anion depends on the sizes of the ions. For example, unlike the other alkali metals the small lithium ion does not form alums, and there is only one sodium alum. In some case solid solutions of alums occur. The sulfate anion, SO42− The structure and bonding of the sulfate ion In inorganic chemistry, a sulfate (IUPAC-recommended spelling; also sulphate in British English) is a salt of sulfuric acid. ... A cation is an ion with positive charge. ... For sodium in the diet, see Salt. ... General Name, symbol, number potassium, K, 19 Chemical series alkali metals Group, period, block 1, 4, s Appearance silvery white Standard atomic weight 39. ... General Name, Symbol, Number rubidium, Rb, 37 Chemical series alkali metals Group, Period, Block 1, 5, s Appearance grey white Standard atomic weight 85. ... General Name, Symbol, Number caesium, Cs, 55 Chemical series alkali metals Group, Period, Block 1, 6, s Appearance silvery gold Standard atomic weight 132. ... General Name, Symbol, Number thallium, Tl, 81 Chemical series poor metals Group, Period, Block 13, 6, p Appearance silvery white Standard atomic weight 204. ... A ball-and-stick model of the ammonium cation Ammonium is also an old name for the Siwa Oasis in western Egypt. ... Methylamine is a simple primary amine with a formula of CH3NH2. ... Hydroxylamine is a reactive chemical with formula NH2OH. It can be considered a hybrid of ammonia and water due to parallels it shares with each. ... Hydrazine is the chemical compound with formula N2H4. ... Aluminum redirects here. ... REDIRECT [[ Insert text]]EWWWWWWWWWWWWW YO General Name, symbol, number chromium, Cr, 24 Chemical series transition metals Group, period, block 6, 4, d Appearance silvery metallic Standard atomic weight 51. ... General Name, symbol, number titanium, Ti, 22 Chemical series transition metals Group, period, block 4, 4, d Appearance silvery metallic Standard atomic weight 47. ... General Name, symbol, number manganese, Mn, 25 Chemical series transition metals Group, period, block 7, 4, d Appearance silvery metallic Standard atomic weight 54. ... General Name, symbol, number vanadium, V, 23 Chemical series transition metals Group, period, block 5, 4, d Appearance silver-grey metal Standard atomic weight 50. ... General Name, symbol, number iron, Fe, 26 Chemical series transition metals Group, period, block 8, 4, d Appearance lustrous metallic with a grayish tinge Standard atomic weight 55. ... For other uses, see Cobalt (disambiguation). ... Not to be confused with Galium. ... General Name, Symbol, Number molybdenum, Mo, 42 Chemical series transition metals Group, Period, Block 6, 5, d Appearance gray metallic Standard atomic weight 95. ... General Name, Symbol, Number indium, In, 49 Chemical series poor metals Group, Period, Block 13, 5, p Appearance silvery lustrous gray Standard atomic weight 114. ... General Name, Symbol, Number Ruthenium, Ru, 44 Chemical series transition metals Group, Period, Block 8, 5, d Appearance silvery white metallic Atomic mass 101. ... General Name, Symbol, Number rhodium, Rh, 45 Chemical series transition metals Group, Period, Block 9, 5, d Appearance silvery white metallic Standard atomic weight 102. ... This article is about the chemical element. ... An anion is an ion with negative charge. ... This article is about the electrically charged particle. ... The alkali metals are a series of elements comprising Group 1 (IUPAC style) of the periodic table: lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr). ... This article is about the chemical element named Lithium. ... Fig. ...

Alums crystallise in one of three different crystal structures. These classes are called α-, β- and γ-alums.

Applications

Alums are useful for a range of industrial processes. They are soluble in water; have an astringent, acid, and sweetish taste; react acid to litmus; and crystallize in regular octahedra. When heated they liquefy; and if the heating is continued, the water of crystallization is driven off, the salt froths and swells, and at last an amorphous powder remains. H2O and HOH redirect here. ... A bottle of tannic acid, an astringent Astringent medicines cause shrinkage of mucous membranes or exposed tissues and are often used internally to check discharge of blood serum or mucous secretions. ... For other uses, see Acid (disambiguation). ... Litmus may refer to: a litmus test Litmus, a test case management tool developed by Mozilla. ... For other uses, see Crystal (disambiguation). ... An octahedron (plural: octahedra) is a polyhedron with eight faces. ... Water of crystallization (alt. ...

Potassium alum is the common alum of commerce, although soda alum, ferric alum, and ammonium alum are manufactured. Potassium alum or potash alum is the potassium double sulfate of aluminium. ... Ammonium alum (NH4Al(SO4)2·12H2O) is a white crystalline double sulfate of aluminium, used in water purification, in vegetable glues, in porcelain cements, in natural deodorants and in tanning, dyeing and in fireproofing textiles. ...

Aluminium sulfate is sometimes called alum in informal contexts, but this usage is not regarded as technically correct. Its properties are quite different from those of the set of alums formally described above. Aluminium sulfate is a widely used industrial chemical. ...

Alchemical and later discoveries and uses

The presence of sulfuric acid in potassium alum was known to the alchemists. J. H. Pott and A. S. Marggraf demonstrated that alumina was another constituent. Pott in his Lithogeognosia showed that the precipitate obtained when an alkali is poured into a solution of alum is quite different from lime and chalk, with which it had been confounded by G.E. Stahl. Marggraf showed that alumina is one of the constituents of alum, but that this earth possesses peculiar properties, and is one of the ingredients in common clay. He also showed that crystals of alum cannot be obtained by dissolving alumina in sulfuric acid and evaporating the solutions, but when a solution of potash or ammonia is dropped into this liquid, it immediately deposits perfect crystals of alum. R-phrases S-phrases , , , Flash point Non-flammable Related Compounds Related strong acids Selenic acid Hydrochloric acid Nitric acid Related compounds Hydrogen sulfide Sulfurous acid Peroxymonosulfuric acid Sulfur trioxide Oleum Supplementary data page Structure and properties n, εr, etc. ... For other uses, see Alchemy (disambiguation). ... This German man was credited (in the West) with discovering a pure form of Zinc ... Aluminium oxide (or aluminum oxide) (Al2O3) is a chemical compound of aluminium and oxygen. ... Making a saline water solution by dissolving table salt (NaCl) in water This article is about chemical solutions. ... This article or section does not adequately cite its references or sources. ... Georg Ernst Stahl (October 21, 1660 - May 24, 1734), was a German chemist and physician. ... For other uses, see Clay (disambiguation). ... Potash Potash (or carbonate of potash) is an impure form of potassium carbonate (K2CO3). ... For other uses, see Ammonia (disambiguation). ...

Torbern Bergman also observed that the addition of potash or ammonia made the solution of alumina in sulfuric acid crystallize, but that the same effect was not produced by the addition of soda or of lime, and that potassium sulfate is frequently found in alum. Torbern Olof Bergman (March 20, 1735 Katrineberg, Sweden, – July 8, 1784 Medevi, Sweden) was a Swedish chemist. ... This article or section does not adequately cite its references or sources. ...

After M.H. Klaproth had discovered the presence of potassium in leucite and lepidolite, it occurred to L.N. Vauquelin that it was probably an ingredient likewise in many other minerals. Knowing that alum cannot be obtained in crystals without the addition of potash, he began to suspect that this alkali constituted an essential ingredient in the salt, and in 1797 he published a dissertation demonstrating that alum is a double salt, composed of sulfuric acid, alumina, and potash. Soon after, J.A. Chaptal published the analysis of four different kinds of alum, namely, Roman alum, Levant alum, British alum and alum manufactured by himself. This analysis led to the same result as Vauquelin. Martin Heinrich Klaproth Martin Heinrich Klaproth (1 December 1743 – 1 January 1817) was a German chemist. ... Leucite or amphigene is a rock-forming mineral composed of potassium and aluminium metasilicate KAl(SiO3)2. ... Crystal of lepidolite, Brazil Lepidolite (KLi2Al(Al,Si)3O10(F,OH)2) is a lilac or rose-violet colored phyllosilicate mineral of the mica group that is a secondary source of lithium. ... Louis Nicolas Vauquelin. ... For other uses, see Mineral (disambiguation). ... Double salts are salts containing more than one cation or anion. ... Jean-Antoine Claude, comte Chaptal de Chanteloup (June 4, 1756 – July 30, 1832), French chemist and statesman, was born at Nogaret, Lozère. ...

Pliny's writings

The word "alumen," which we translate "alum," occurs in Pliny's Natural History. In the 15th chapter of his 35th book he gives a detailed description of it. By comparing this with the account of stupteria given by Dioscorides in the 123rd chapter of his 5th book, it is obvious that the two are identical. Pliny informs us that alumen was found naturally in the earth. He calls it salsugoterrae. Different substances were distinguished by the name of "alumen"; but they were all characterized by a certain degree of astringency, and were all employed in dyeing and medicine, the light-colored alumen being useful in brilliant dyes, the dark-colored only in dyeing black or very dark colors. One species was a liquid, which was apt to be adulterated; but when pure it had the property of blackening when added to pomegranate juice. This property seems to characterize a solution of iron sulfate in water; a solution of ordinary (potassium) alum would possess no such property. Pliny says that there is another kind of alum that the Greeks call schistos. It forms in white threads upon the surface of certain stones. From the name schistos, and the mode of formation, there can be little doubt that this species was the salt which forms spontaneously on certain salty minerals, as alum slate and bituminous shale, and which consists chiefly of sulfates of iron and aluminium. Possibly in certain places the iron sulfate may have been nearly wanting, and then the salt would be white, and would answer, as Pliny says it did, for dyeing bright colors. Several other species of alumen are described by Pliny, but we are unable to make out to what minerals he alludes. Pliny the Elder: an imaginative 19th Century portrait. ... Pedanius Dioscorides (ca. ... For the color, see Pomegranate (color). ... The sulfate anion, SO42− The structure and bonding of the sulfate ion In inorganic chemistry, a sulfate (IUPAC-recommended spelling; also sulphate in British English) is a salt of sulfuric acid. ... For other uses, see Slate (disambiguation). ... Shale Shale is a fine-grained sedimentary rock whose original constituents were clays or muds. ...

The alumen of the ancients, then, was not the same as the alum of the moderns. It was most commonly an iron sulfate, sometimes probably an aluminium sulfate, and usually a mixture of the two. But the ancients were unacquainted with our alum. They were acquainted with a crystallized iron sulfate, and distinguished it by the names of misy, sory, and chalcanthum. As alum and green vitriol were applied to a variety of substances in common, and as both are distinguished by a sweetish and astringent taste, writers, even after the discovery of alum, do not seem to have discriminated the two salts accurately from each other. In the writings of the alchemists we find the words misy, sory, chalcanthum applied to alum as well as to iron sulfate; and the name atramentum sutorium, which ought to belong, one would suppose, exclusively to green vitriol, applied indifferently to both. Various minerals are employed in the manufacture of alum, the most important being alunite or alum-stone, alum schist, bauxite and cryolite. Iron(II) sulfate is the chemical compound with the formula (FeSO4). ... For other uses, see Alchemy (disambiguation). ... For other uses, see Mineral (disambiguation). ... Schist The schists form a group of medium-grade metamorphic rocks, chiefly notable for the preponderance of lamellar minerals such as micas, chlorite, talc, hornblende, graphite, and others. ... This article is about the ore. ... It has been suggested that this article or section be merged with sodium hexafluoroaluminate. ...

Early uses in industry

Alum was imported into England mainly from the Middle East, and, from the late 15th Century onwards, the Papal States for hundreds of years. Its use there was as a dye-fixer (mordant) for wool (which was one of England's primary industries), the value of which increased significantly if dyed. These sources were unreliable, however, and there was a push to develop a source in England. With state financing, attempts were made throughout the 16th Century, but without success until early on in the 17th Century. An industry was founded in Yorkshire to process the shale which contained the key ingredient, aluminium sulfate, and made an important contribution to the Industrial Revolution. Alum (Known as turti in local Indian languages) was also used for water treatment by Indians for hundreds of years. (14th century - 15th century - 16th century - other centuries) As a means of recording the passage of time, the 15th century was that century which lasted from 1401 to 1500. ... Look up dye in Wiktionary, the free dictionary. ... Look up Mordant in Wiktionary, the free dictionary. ... For other uses, see Wool (disambiguation). ... (15th century - 16th century - 17th century - more centuries) As a means of recording the passage of time, the 16th century was that century which lasted from 1501 to 1600. ... (16th century - 17th century - 18th century - more centuries) As a means of recording the passage of time, the 17th century was that century which lasted from 1601-1700. ... Yorkshire is a historic county of northern England. ... Aluminium sulfate is a widely used industrial chemical. ... A Watt steam engine, the steam engine that propelled the Industrial Revolution in Britain and the world. ...

Production

Alum from alunite

In order to obtain alum from alunite, it is calcined and then exposed to the action of air for a considerable time. During this exposure it is kept continually moistened with water, so that it ultimately falls to a very fine powder. This powder is then lixiviated with hot water, the liquor decanted, and the alum allowed to crystallize. The alum schists employed in the manufacture of alum are mixtures of iron pyrite, aluminium silicate and various bituminous substances, and are found in upper Bavaria, Bohemia, Belgium, and Scotland. These are either roasted or exposed to the weathering action of the air. In the roasting process, sulfuric acid is formed and acts on the clay to form aluminium sulfate, a similar condition of affairs being produced during weathering. The mass is now systematically extracted with water, and a solution of aluminium sulfate of specific gravity 1.16 is prepared. This solution is allowed to stand for some time (in order that any calcium sulfate and basic ferric sulfate may separate), and is then evaporated until ferrous sulfate crystallizes on cooling; it is then drawn off and evaporated until it attains a specific gravity of 1.40. It is now allowed to stand for some time, decanted from any sediment, and finally mixed with the calculated quantity of potassium sulfa te (or if ammonium alum is required, with ammonium sulfate), well agitated, and the alum is thrown down as a finely-divided precipitate of alum meal. If much iron should be present in the shale then it is preferable to use potassium chloride in place of potassium sulfate. Alunite, or alumstone, is a mineral that was first observed in the 15th century at Tolfa, near Rome, where it was mined for the manufacture of alum. ... The mineral pyrite, or iron pyrite, is iron sulfide, FeS2. ... In chemistry, a silicate is a compound containing an anion in which one or more central silicon atoms are surrounded by electronegative ligands. ... For other uses, see Bavaria (disambiguation). ... Flag of Bohemia Bohemia (Czech: ; German: ) is a historical region in central Europe, occupying the western and middle thirds of the Czech Republic. ... This article is about the country. ... Weathering is the decomposition of rocks, soils and their minerals through direct contact with the Earths atmosphere. ... Relative density (also known as specific gravity) is a measure of the density of a material. ...

Alum from clays or bauxite

In the preparation of alum from clays or from bauxite, the material is gently calcined, then mixed with sulfuric acid and heated gradually to boiling; it is allowed to stand for some time, the clear solution drawn off and mixed with acid potassium sulfate and allowed to crystallize. When cryolite is used for the preparation of alum, it is mixed with calcium carbonate and heated. By this means, sodium aluminate is formed; it is then extracted with water and precipitated either by sodium bicarbonate or by passing a current of carbon dioxide through the solution. The precipitate is then dissolved in sulfuric acid, the requisite amount of potassium sulfate added and the solution allowed to crystallize. For other uses, see Clay (disambiguation). ... This article is about the ore. ... It has been suggested that this article or section be merged with sodium hexafluoroaluminate. ... Calcium carbonate is a chemical compound, with the chemical formula CaCO3. ... Flash point Non-flammable. ... Carbon dioxide is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. ...

Types of alum

Soda alum

Sodium alum, Na₂SO₄·Al₂(SO₄)₃·24H₂O, mainly occurs in nature as the mineral mendozite. It is very soluble in water, and is extremely difficult to purify. In the preparation of this salt, it is preferable to mix the component solutions in the cold, and to evaporate them at a temperature not exceeding 60 °C. 100 parts of water dissolve 110 parts of sodium alum at 0 °C, and 51 parts at 16 °C. Soda alum is used in the acidulent of food as well as in the manufacture of baking powder. Mendozite is a sulfate mineral, one of the alum series with formula: NaAl(SO4)2·11H2O. It was discovered in Mendoza Province, Argentina in 1868, it occurs in evaporites and is unlikely to be found anywhere except in extremely dry conditions. ...

Ammonium alum

Ammonia alum, NH₄Al(SO₄)₂·12H₂O, a white crystalline double sulfate of aluminium, is used in water purification, in vegetable glues, in porcelain cements, in natural deodorants (though potassium alum is more commonly used), in tanning, dyeing and in fireproofing textiles. Ammonium alum (NH4Al(SO4)2·12H2O) is a white crystalline double sulfate of aluminium, used in water purification, in vegetable glues, in porcelain cements, in natural deodorants and in tanning, dyeing and in fireproofing textiles. ...

Alum solubility

The solubility of the various alums in water varies greatly, sodium alum being readily soluble in water, while caesium and rubidium alums are only sparingly soluble. The various solubilities are shown in the following table. General Name, Symbol, Number caesium, Cs, 55 Chemical series alkali metals Group, Period, Block 1, 6, s Appearance silvery gold Standard atomic weight 132. ... General Name, Symbol, Number rubidium, Rb, 37 Chemical series alkali metals Group, Period, Block 1, 5, s Appearance grey white Standard atomic weight 85. ...

At temperature T, 100 parts water dissolve:

Selenate containing alumns

Alums are also known that contain selenium in place of sulfur. They are called selenium- or selenate-alums.

Uses

• Makeup: Alum was often used as a base in skin whiteners and treatments during the late 16th Century in the Elizabethan fashion. This is an example of a recipe:

"For the Freckles which one getteth by the heat of the Sun: Take a little Allom beaten small, temper amonst it a well brayed white of an egg, put it on a milde fire, stirring it always about that it wax not hard, and when it casteth up the scum, then it is enough, wherewith anoint the Freckles the space of three dayes: if you will defend your self that you get no Freckles on the face, then anoint your face with the whites of eggs." Christopher Wirzung, General practise of Physicke, 1654.

• Shaving alum: is a powdered form of alum used as an astringent to prevent bleeding from small shaving cuts. The styptic pencils sold for this purpose contain aluminium sulfate or potassium aluminium sulfate. Similar products are also used on animals to prevent bleeding after nail-clipping. Alum in block form (usually potassium alum) is used as an aftershave, rubbed over the wet freshly shaved face.

• Hair Stiffener: Alum was used in rock form in the 1950's to rub on the front short hair of a "crewcut". When the hair dried, it would stay up all day.

• Crystal deodorant: Alum was used in the past as a natural underarm deodorant in Europe, Mexico, Thailand, the Far East and in the Philippines where it is called Tawas. It is now commercially sold for this purpose in many countries, often in a plastic case that protects the crystal and makes it resemble other non-liquid deodorants. Typically potassium alum is used.

• Alum powder, found amongst spices at most grocery stores, is used in pickling recipes as a preservative, to maintain crispness, and as an ingredient in some play dough recipes. It is also commonly cited as a home remedy or pain relief for canker sores.

• Fire retardant: By soaking and then drying cloth and paper materials they can be made fireproof.

• Wax: Alum is used in the Middle East as a component in wax, compounded with other ingredients to create a hair-removal substance.

• Foamite: Alum is used to make foamite which is used in many fire extinguishers for chemical and oil fires.

• Adjuvant: Alum is used regularly as an adjuvant (enhances immune response to a given immunogen when given with it) in human immunizations.

• Antibacterial agent: Alum works as a deodorant because Alum inhibits bacterial growth. This fits the definition of an antibacterial agent. Styptic pencils or Alum powder/crystals can be applied to cuts that have a mild infection.

A bottle of tannic acid, an astringent Astringent medicines cause shrinkage of mucous membranes or exposed tissues and are often used internally to check discharge of blood serum or mucous secretions. ... A styptic or hemostatic pencil is a short stick of medication, usually containing alum, which is used for staunching blood by causing blood vessels to contract at the site of the wound. ... Roll-on deodorant Rexona Degree brand Stick deodorant Deodorants (Deodourants) are substances applied to the body, most frequently the underarms, to reduce the body odor caused by the bacterial breakdown of perspiration. ... Ammonium alum (NH4Al(SO4)2·12H2O) or ammonium aluminum sulfate dodecahydrate is a white crystalline double sulfate of aluminium, used in water purification, in vegetable glues, in porcelain cements, in natural deodorants and in tanning, dyeing and in fireproofing textiles. ... A mouth ulcer or canker sore is a painful open sore inside the mouth caused by a break in the mucous membrane. ... In immunology an adjuvant is an agent which, while not having any specific antigenic effect in itself, may stimulate the immune system, increasing the response to a vaccine. ...

Related compounds

In addition to the alums, which are dodecahydrates, double sulfates and selenates of univalent and trivalent cations occur with other degrees of hydration. These materials may also be referred to as alums, including the undecahydrates such as mendozite and kalinite, hexahydrates such as guanidinium (CH₆N₃⁺) and dimethylammonium (CH₃)₂NH₂⁺) "alums", tetrahydrates such as goldichite, monohydrates such as thallium plutonium sulfate and anhydrous alums (yavapaiites). These classes include differing, but overlapping, combinations of ions. Mendozite is a sulfate mineral, one of the alum series with formula: NaAl(SO4)2·11H2O. It was discovered in Mendoza Province, Argentina in 1868, it occurs in evaporites and is unlikely to be found anywhere except in extremely dry conditions. ... Kalinite is a mineral form of aluminium potassium sulphate Al2(SO4)3 â‹… K2SO4 â‹… 24H2O. This compound is used in a wide variety of processes such as the manufacture of dyes, explosives, and porcelain cement, tanning, hardening gelating and purifying water. ... Guanidine is a crystalline compound of strong alkalinity formed by the oxidation of guanine. ... Safety (MSDS) data for dimethylamine General Synonyms: N-methyl-methanamine Molecular formula: C2H7N CAS No: 124-40-3 EINECS No: 204-697-4 EC index no: 612-001-00-9 Physical data Appearance: colourless gas with strong ammonia-like smell Melting point: -92 C Boiling point: 7. ...

A pseudo alum is a double sulfate of the typical formula ASO₄·B₂(SO₄)₃·22H₂O, where A is a divalent metal ion, such as cobalt (wupatkiite), manganese (apjohnite), magnesium (pickingerite) or iron (halotrichite or feather alum), and B is a trivalent metal ion. For other uses, see Cobalt (disambiguation). ... General Name, symbol, number manganese, Mn, 25 Chemical series transition metals Group, period, block 7, 4, d Appearance silvery metallic Standard atomic weight 54. ... General Name, symbol, number magnesium, Mg, 12 Chemical series alkaline earth metals Group, period, block 2, 3, s Appearance silvery white solid at room temp Standard atomic weight 24. ... General Name, symbol, number iron, Fe, 26 Chemical series transition metals Group, period, block 8, 4, d Appearance lustrous metallic with a grayish tinge Standard atomic weight 55. ... A sample of Halotrichite Halotrichite, also known as feather alum, is a highly hydrated sulfate of aluminium and iron. ...

A Tutton salt is a double sulfate of the typical formula A₂SO₄·BSO₄·6H₂O, where A is a univalent cation, and B a divalent metal ion.

In popular culture

Gags in which someone ingests alum, either accidentally self-administered or surreptitiously administered by another, resulting in exaggerated effects, are a traditional staple of comedy. In live-action comedies, effects on the victim usually include extreme puckering of the mouth and lips and tightening of the throat. An example of this is in the Three Stooges short "No Census, No Feeling" when Curly is making a fruit punch and thinking it was sugar, puts alum in the fruit punch. The Three Stooges was an American comedy act in the 20th century. ...

In animated cartoons, the effects are normally expanded to include extreme shrinking of the head.

Thomas Pynchon borrows the joke in chapter 16 of his 1963 novel V., in a scene where alum is slipped into the beer of a jazz trumpet player.

See also

• List of minerals
• Potash alum

Gem animals. ... For alum meaning graduate, see Alumn. ...

References

1. ^ Greenwood, N. N.; & Earnshaw, A. (1997). Chemistry of the Elements (2nd Edn.), Oxford:Butterworth-Heinemann. ISBN 0-7506-3365-4.