- The siege of Jerusalem (c. 589–587 BC) was the final event of the Judahite revolts against Babylon, in which Nebuchadnezzar II, king of the Neo-Babylonian Empire, besieged Jerusalem, the capital city of the Kingdom of Judah. Jerusalem fell after a 30-month siege, following which the Babylonians systematically destroyed the city and Solomon’s Temple. The Kingdom of Judah was dissolved and many of its inhabitants exiled to Babylon.
- Silicon dioxide (Wikipedia)
Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula SiO2, commonly found in nature as quartz. In many parts of the world, silica is the major constituent of sand. Silica is one of the most complex and abundant families of materials, existing as a compound of several minerals and as a synthetic product. Examples include fused quartz, fumed silica, opal, and aerogels. It is used in structural materials, microelectronics, and as components in the food and pharmaceutical industries. All forms are white or colorless, although impure samples can be colored.