This is a compound of no great importance in a medico-legal point of
view. Nevertheless an instance has been lately published in which it was
taken for the purpose of committing suicide, and was found abundantly in
the stomach.[1049] The carbonate of copper exists naturally in two
states. In one form it constitutes the rust of copper, or natural
verdigris, and is produced as a powdery crust on metallic copper by long
exposure to moist air. It is insipid and insoluble, so that pure water
left in vessels incrusted with it does not become poisonous. It
dissolves with effervescence in sulphuric acid, and without
effervescence in ammonia, forming the usual violet solution. In another
form it exists in the mineral kingdom, constituting the chief part of a
beautiful ore, malachite, and also a considerable proportion of some
blue-copper ores.