CARBON AND CARBONATES
Carbon compounds enter so largely into the structure of organised bodies that their chemistry is generally considered apart from that of the other elements under the head of _Organic Chemistry_. Carbon occurs, however, among minerals not only in the oxidised state (as carbonates), but also in the elementary form (as in diamond and graphite), and combined with hydrogen, oxygen, &c. (as in petroleums, bitumens, lignites, shales, and coals). In small quantities "organic matter" is widely diffused in minerals and rocks. In shales and clays it may amount to as much as 10 or 20 per cent. (mainly as bituminous and coaly matters). The assayer has only to take account of the organic matter when it is of commercial importance, so that in assays it is generally included under "loss on ignition." Much more according to this >> |
Previous
Home
