Alum (pronounced /ˈæləm/) is both a specific chemical compound and a class of chemical compounds. The specific compound is the hydrated potassium aluminium sulfate (Potassium alum) with the formula KAl(SO4)2.12H2O. The wider class of compounds known as alums have the related empirical formula, AB(SO4)2.12H2O.
Edwin Jagger - Antiseptic Alum Block
in box
DETAILS: Wet block with cold water and apply to affected area. Alum is an old fashioned antiseptic that arrests bleeding by acting as a blood coagulant- soothes redness and razor burn associated with wet shaving. 54 grams.  Handcrafted from natural ingredients in Sheffield, England.

Cosmetic Uses:

  • Alum in block form (usually potassium alum) is used as a blood coagulant. It is widely used after shaving, rubbed over the wet freshly shaved face.
  • Styptic pencils containing aluminium sulfate or potassium aluminium sulfate are used as astringents to prevent bleeding from small shaving cuts.
  • Alum was used as a base in skin whiteners and treatments during the late 16th century. A recipe for one such compound was given thus:
    "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
  • In the 1950s, men sporting crewcut or flattop hairstyles sometimes applied alum to their front short hairs as an alternative to pomade[citation needed]. When the hair dried, it would stay up all day.
  • Alum's antibacterial properties contribute to its traditional use as an underarm deodorant. It has been used for this purpose in Europe; Mexico; Thailand, where it is called Sarn-Som; throughout Asia; and in the Philippines, where it is called Tawas. Today, potassium alum is sold commercially for this purpose as a "deodorant crystal," often in a protective plastic case.
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