Pewter of the Bronze Age in the Near East. The earliest piece of pewter found is from an Egyptian tomb from 1450 BC. The constituents of pewter were first controlled in the 12th century by town guilds in France. By the 15th century, the Worshipful Company of Pewterers controlled pewter constituents in England. This company originally had two grades of pewter, but in the 16th century a third grade was added. The first type, known as "fine metal", was used for tableware. It consisted of tin with as much copper as it could absorb, which is about 1%. The second type,
Photon etc. Photon etc. Photon etc. is a Canadian manufacturer of infrared cameras, hyperspectral imaging and spectroscopic scientific instruments for academic and industrial applications. Its main technology is based on volume Bragg gratings, which are used as filters either for swept lasers or for global imaging. As a spin-off of the California Institute of Technology, the company was founded in 2003 by Sébastien Blais-Ouellette who was working on narrow band imaging tunable filters for the detection of hydroxyl groups in the Earth atmosphere. This is how he developed the main technology of the company, a patented volume Bragg grating for filtering purposes.