1 2 Carbon 61·01 69·04 Alumina 7·80 6·86 Silica 17·34 14·18 Magnesia 1·03 0·53 Lime 2·56 0·80 Ferric oxide 5·54 4·00 Potash 0·87 0·91 Water and volatiles 3·24 2·89 Sulphur 0·51 0·62 GRAPHITES FROM UPPER STYRIA 1 2 3 Carbon 85·00 87·16 82·21 Ash 14·89 12·66 17·92 4 5 6 Carbon 82·40 81·10 55·50 Silica 12·38 11·61 21·00 Alumina 3·90 5·60 14·56 Ferric oxide 0·53 Manganese protoperoxide 0·62 2·00 4·84 Lime 0·02 2·00 4·84 Alkalis Trace Trace 0·62 Sulphur -- -- 0·30 Loss on incineration -- -- 2·43 Of these Styrian specimens, Nos. 1–4 are crude kinds, of sp. gr. 2·1443; No. 5 was levigated in the laboratory, and No. 6 was levigated from an inferior quality at the mine. According to the character of the crystalline structure, the colour of graphite varies, but is mostly deep black. Very pure specimens, such as the beautiful graphite blocks (from the renowned Alibert graphite mines in Siberia) which, as a rule, are only to be seen in exhibitions and mineralogical collections, have the appearance of unpolished steel or white pig iron (spiegeleisen). The most important property of native graphite is its low hardness and cohesion, in consequence of which it leaves a streak when drawn over the surface of paper. Graphite seems to be of frequent occurrence all over the world, though only few deposits are known which yield a product that is suitable for all the purposes to which graphite is applied.