Various forms of
calcium sulphate have been used as building materials since the
Bronze Age, and other sulphates have been utilized since at least antiquity. However, the first salts of this group were chemically described only in the 17th century. The production of sulphuric acid esters, as well as their biological significance and natural occurrence, has been known only since the 19th century.In the eastern Mediterranean and the
Middle East, the use of
mortar was widespread thousands of years ago. In ancient Egypt, its application is documented as early as the third millennium BC. Archaeological sites demonstrating its use include the
Old Palace of Aššur and the ruins of
Amarna. In the
Parthian Empire, plaster mortar was employed in the construction of vaults. From the period of the
Roman Empire until the 19th century,
lime mortar (containing
calcium carbonate) was far more widely used, although gypsum mortar continued to be applied to a limited extent during the Middle Ages, for example in France. The use of calcium sulphate in
cement has been investigated since the late 19th century and has been widely adopted since the 1930s. During the Bronze Age,
alabaster was extensively used for decorative architectural elements in the
Minoan culture. Toward the end of the Bronze Age, gypsum alabaster from Cretan quarries was exported and used elsewhere, for example for benches in
Mycenae. In the ruins of
Akrotiri on
Santorinii, it was used for floor tiles.
Alabaster is easily worked and became a common and highly valued material for sculptures and monuments during the Middle Ages and the modern period. It was quarried primarily in central England, northern Spain, and the French Alps, and traded over long distances. In 1550, religious sculptures were banned in England (see
Reformation iconoclasm), leading to the large-scale export of alabaster figures to France. Some sulfates were known to alchemists. The vitriol salts, from the Latin
vitreolum, glassy, were so-called because they were some of the first transparent crystals known.
Green vitriol is
iron(II) sulfate heptahydrate, ;
blue vitriol is
copper(II) sulfate pentahydrate, and
white vitriol is zinc sulfate heptahydrate, .
Alum, a double sulfate of
potassium and
aluminium with the formula , figured in the development of the chemical industry. Sulphates were historically used as dyes and pigments. In
Ancient Egypt,
anhydrite screed and
jarosite, KFe3[(OH)6(SO4)2], were employed in wall decoration. The pigment jarosite has also been identified in Central America in vessels from a burial site in
Teotihuacán. The use of
iron gall ink was widespread during the Middle Ages and continued into the modern era. It was prepared from
plant gall and
iron(II) sulphate.
Alum (potassium aluminum sulfate) was formerly used in leather production (tanning), possibly as early as ancient Egypt. It was certainly known in classical antiquity in Rome and Greece. The first sulphuric acid salts were identified as such in the 17th century.
Sodium sulphate, specifically its decahydrate known as ''Glauber's salt
, was described around 1625 by Johann Rudolph Glauber. He analyzed water from a medicinal spring near Naples and isolated sodium sulphate, which he named Sal mirabile''. Several years later, he determined that sodium sulphate could be produced from
rock salt (
sodium chloride) and
sulphuric acid.
Magnesium sulphate obtained from a mineral spring in
Epsom, England, was scientifically described at the end of the 17th century. Both the spring water and the isolated salt exhibited medicinal properties and were used as a laxative and for the treatment of headaches. The medical application of plaster for the treatment of
bone fracture began in the early 19th century. Initially, wooden boxes filled with cast plaster were used. Although widespread in Europe, this method was impractical because the heavy plaster constructions confined patients to bed. Plaster-impregnated bandages for
plaster casts were introduced in the mid-19th century and were initially prepared fresh in hospitals. Ready-to-use plaster bandages did not become commercially available until the 1930s. Another important medical development was the use of
magnesium sulphate for the treatment of seizures during pregnancy (
eclampsia). This application was first reported in 1916. By 1930, magnesium sulphate had largely replaced less suitable treatments, such as
opioids, and contributed significantly to the reduction of
maternal mortality. ==Environmental effects==