The mineral industry of the British Empire and foreign countries : statistical summary (production, imports and exports) 1929-1931

Throughout the trade statistics in this document, materials imported or exported on government account have been included as far as possible. Trade statistics for the United Kingdom include the trade of Great Britain and Northern Ireland with the Irish Free State, and exclude the direct foreign trade of the Irish Free State, which is given separately. Export statistics for Germany include deliveries on reparations account. Trade statistics for Japan do not include trade between that country and the rest of the Japanese Empire. Trade figures for Korea and Formosa include the trade with all other parts of the Japanese Empire. Production statistics in the case of Bavaria refer only to that part of Bavaria lying to the east of the Rhine. The units of quantity adopted are the British statute cwt. and ton of 112 lb. (avdp.) and 2,240 lb. (avdp.) respectively, the imperial gallon and the metric carat. For precious metals the troy ounce of 480 grains is used.