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NATURAL HISTORY OF TIN,

ClaSS IV.. ..VERY DUCTILE AND EASILY OXIDABLE METALS.'

TIN.

PART XLIX.

SECT. I.

NATURAL HISTORY OF TIN.

It has been much doubted whether tin is ever found native.In the opinion of Kirwan there are sufficient authorities to deter-mine the question in the affirmative. The native otdd of tin , ortin stone, occurs both massive and crystallized. Its colour is adark brown, sometimes yellowish grey. When crystallized, itis somewhat transparent. The wood tin ore is a variety of thenative oxid, termed so from its fibrous texture. This variety hashitherto been found only in Cornwall. It occurs in fragmentswhich are generally round, and its colour is brown, sometimesinclining to yellow. Tin is also found mineralized by sulphur,associated always with a portion of copper, and often of iron.