Copper Stannate
:
ON THE SECONDARY, GREEN.
or Tin-Copper Green, equals in colour any of the copper greens free from
arsenic. The cheapest way of making it is to heat 59 parts of tin in a
Hessian crucible with 100 parts nitrate of soda, and dissolve the mass
when cold in a caustic alkali. To the clear solution, diluted with
water, a cold solution of sulphate of copper is added: a reddish-yellow
precipitate falls, which on being washed and dried, becomes a beautiful
green. On the palette it would be superfluous, but for common purposes
might be found of service.