White tin is refined metallic tin.
It contrasts with black tin, which is unrefined tin ore (cassiterite) as extracted from the ground. The term "white tin" was historically associated with tin mining in Devon and Cornwall where it was smelted from black tin in blowing houses.
White tin may also refer specifically to β-tin, the metallic allotrope of the pure element, as opposed to the nonmetallic allotrope α-tin (also known as gray tin), which occurs at temperatures below 13.2 °C (55.8 °F), a transformation known as tin pest). White tin has tetragonal unit cell.
References[edit]
- Chambers's encyclopædia: A dictionary of universal knowledge. 1868. p. 448.
- Blanchard, Ian (2005). Mining, Metallurgy, and Minting in the Middle Ages: Continuing Afro-European Supremacy, 1250-1450. Franz Steiner Verlag. p. 1526. ISBN 9783515087049.
- Carew, Richard (1811). Carew's Survey of Cornwall: To which are added, notes illustrative of its history and antiquities. p. 40.
- Rickard, William (1859). The miner's manual of arithmetic and surveying ...: With a compendium of mensuration and a concise treatise on practical geometry and plane trigonometry; also a course of mine surveying ... Together with levelling and land surveying. p. 38.
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction