2612 Table 2 - Distribution of C-resources by quality in Mio t Quality CResources all Share in % CResources producing operations only Share in % CResources exploration projects only Share in % Cryptocryst. ”amorphous ”) 581, 4 33,07 21.8 6.55 0.05 0.01 Flake, mixed 1129,7 64.26 287.9 86.49 671.5 98.88 Lumps 29,0 1,65 23.0 6.91 1,5 0.22 Unknown quality 17,9 1.02 0.17 0.05 6,0 0.89 total 1 758.0 100 332.8 100 679,1 100 Nearly two-thirds of global deposit resources contain flake-grade graphite. Table 2 clearly shows that almost all exploration projects are focused on deposits of this quality. 5.1.3 by age of mineralisation Table 3 - Distribution of C-resources by age of mineralisation in Mio t Age of mineralisation CResources all Share in % CResources producing operations only Share in % CResources exploration projects only Share in % Archaic 138.0 7.85 97.1 29.16 9.14 1.39 Paleoproteroc oic 192.8 10.97 29.6 8.91 113.4 16.71 Mesoproteroc oic 51.3 2.92 0.2 0.06 24.6 3.62 Neoproterocoi c 558.1 31.74 142.2 42.74 393.8 57.99 Prot. undiff. 31.7 1.8 0.16 0.05 9.3 1.37 Cambrian 2.1 0.12 1.44 0.43 0.7, 0.1 Ordovocian 0 0 0 0 0 0 Silurian 0 0 0 0 0 0 Devonian 0 0 0 0 0 0 Carboniferous 592.4 33.70 19.6 5.89 66.2 9.76 Permian 16.9 0.97 16.2 4.88 0 0 Pal. undiff. 1.5 0.08 0 0 1.5 0.22 Triassic 43.5 2.47 1.5 0.45 0 0 Jurassic 0 0 0 0 0 0 Cretaceous 2.5 0.14 0 0 0 0 Paleogene 0 0 0 0 0 0 Neogene 0 0 0 0 0 0 Pleistocene 8.5 0.49 0 0 8.5 1.26 Unknown 118.6 6.75 0 7.43 51.6 7.6 Total 1758.0 100 332.8 100 679.1 100 Proterocoic, in particular Neoproterozoic, sediments are by far the most important graphite-bearing rock sequences. During this period, organic material, which served as the basis for the graphites formed during metamorphism, was able to accumulate massively. Those areas are preferred exploration targets.
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