136 BULLETIN 118, UNITED STATES NATIONAL MUSEUM. 



KIMBERLEY SHAFT. 



Museum 

 number. 



75939 

 75940 

 75941 

 75942 

 75943 

 75944 

 75945 

 75946 

 75947 

 75948 

 75949 

 75950 

 75951 

 75952 

 75953 

 75954 

 75955 

 75956 

 75957 

 75958 

 75959 



Kind of rock. 



Quaxtzite 



Altered shale 



Mixture, quartzite, etc. . . 

 Diabase with amygdaloid . 

 Quartz porphvrv 



do *..: 



Basalt dike 



Porphyry (?) 



Quartz porphyry 



do 



do 



Basalt dike 



Metamorphosed shale. . . . 



Shales 



Dyke 



Soft blue ground 



Hard blue ground 



do 



Concentrates. 



Position in 

 shaft. 



Feet. 

 1,000 

 1,200 

 1,200 

 1,520 

 1,520 

 1,520 

 1,840 

 1,840 

 1,840 

 2,160 

 2,160 

 2,160 

 2,470 

 2,500 

 2,560 

 2,000 

 1,840 

 2,520 



BULLFONTEIN SHAFT. 



75960 

 75961 

 75962 

 75963 

 75964 

 75965 

 75966 

 75967 

 75968 



Peridotite 



Quartzite 



Olivine diabase 



Blue ground 



Blue ground north side of mine. 

 Blue ground south side of mine. 



Concentrates 



200 

 600 

 600 

 400 

 600 

 600 



PREMIER MINE. 



75969 



75970 

 75971 

 75972 

 75973 

 75974 



Blue ground south side of mine. 

 Blue ground north side of mine. 

 Blue ground open mine 



Concentrates 



500 

 500 

 300 



3. GRANITE PEGMATITES AND THEIR ASSOCIATED MINERALS. 



The term "pegmatite " is applied to an interesting and peculiar type 

 of igneous rock which occurs in the form of intrusive dikes and sheets, 

 and is characterized as a rule by a coarse and extremely variable 

 crystallization. The granite pegmatites consist for the most part 

 of the same minerals as compose ordinary granite — that is, of quartz 

 and feldspar, with or without mica — but are often accompanied by a 

 considerable number of accessory minerals, which make them favorite 

 hunting grounds for the collector. Crystallization sometimes takes 



