EARLIST APPLIED CHEMISTRY




The earliest applications of chemical processes were concerned with extraction and working of metals and manufacture of pottery. These arts were carried out without any theoretical background, but often with considerable skill. Before the finding of metals, usually their implements were made of stone, horn or bone.

The 1st metal known was probably gold. This metal occurs in the native mettalic form in some river sands and would attract attention by its color and luster. The earliest gold was probably obtained as a small nuggets by washing alluvial deposit.

Fig 1. Gold washing in ancient Egypt (4000 BC)

The next metal known was probably copper and some think it was known even before gold in Egypt. The Egyptian copper was probably obtained by reducing the ore malachite (the basic copper carbonate) from Sinai in charcoal fires.

Fig 2. Sumerian copper statuette (3300 BC)

The earliest known working in metals appears before 3400 BC in Egypt and Mesopotamia, and rather later in the island of Crete, in the Mediterranean. Egypt and Mesopotamia are rivals in the claim for the origin of the working of metals. The Sumerians (the ancient inhabitants of Mesopotamia) were expert in the working of gold, silver and copper.

Fig 3. Silver vase of Entemena (2850 BC)

Gold and copper also occurs in the island of Crete, which was the centre of an old civilization known as the Minoan. The Cretans probably learnt the use of metal frop Egypt, with which the were in relation from the earliest times.

Fig 4. Minoan Gold Cup (1500 BC)

A great advance in metal working was the invention of bronze, an alloy of copper and tin. The earliest Egyptian bronze is dating to about 3000 BC. The big question : “Where did the tin came from?” (nowadays, there are no tin mines in both of Egypt and Mesopotamia) Egyptian and Mesopotamian bronzes sometimes contain lead in place of tin and sometimes aantimony (as do some early Chinese bronzes).

The metal iron, silver and lead were also known in Egypt, soon after copper and gold (about 3400 BC).

Fig 5. Egyptian Metal Working (a copper vase)

The early iron was very scarce and was probably (since it contains nickel) obtained from meteorites. Iron tools were found in the pyramid of Cheops (2900 BC) and do not contain nickel. Iron was used sparingly in Egypt about 2000 BC, which come from the Land of the Hitties, in Asia Minor, around the Black Sea. The Hittites promising a steel dagger and asking for gold in exchange.

The metal Orichalcum (mentioned by Plato), may have been brass, was found in Palestine at 1200 BC.

Fig 6. Roman’s Coin, made from brass (100 M)

The Egyptian potter very soon learnt the use of the wheel for moulding the clay and the vessels were baked in tall closed furnaces, not in open fire.

Fig 7. Egyptian making pottery with furnace

The manufacture of glass on the large scale apparently bagan in Egypt about 1370 BC. The alkali (natron, sodium carbonate found in Egyptian lakes near Alexandria) was melted with crushed quartz in crucibles.
A deep blue color (“Egyptian blue”) was made in Egypt by heating silica with malachite and lime in the temperature range 830 –90o oC.
Some early speciments of Egyptian and Babylonian blue glass are colored with cobalt.


Source : 
History of Chemistry materials
International Chemistry Education 2011
Yogyakarta State University 

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