Meddelelser om Grønland . The prismatic faces are perpendicu-larly striated to a very high degree; theother faces are generally rather dull, which,I think, may be due to the fact, that thecalcite that has originally surrounded them,is resolved. Fig-?. Ilvaite, type 64 With this type is connected a number of smaller crystals(1—10°), partly placed between the larger ones, and in manyrespects approaching as well the preceding type as the followingone. The form becomes broader by 6^{l40) being pressed backby the other prismatic faces, £(43l} most frequently becomeslarger; further is added e{02
Meddelelser om Grønland . The prismatic faces are perpendicu-larly striated to a very high degree; theother faces are generally rather dull, which,I think, may be due to the fact, that thecalcite that has originally surrounded them,is resolved. Fig-?. Ilvaite, type 64 With this type is connected a number of smaller crystals(1—10°), partly placed between the larger ones, and in manyrespects approaching as well the preceding type as the followingone. The form becomes broader by 6^{l40) being pressed backby the other prismatic faces, £(43l} most frequently becomeslarger; further is added e{02l), /{04l}, ä:{41i}, and s{l2l}.The most characteristic feature of the type is always the pre-sence of the form C(33l}; on the other hand ?:;{2?) disappearsin most of the crystals. Type XI represents among all the crystals of ilvaite those richest in this type belong only small crystals (I—2°) exclusivelyimbedded in calcite. The occurrence is very characteristic bythe fact that the crystals of the immediately adjoining cavities where no calcite is found, belong totype I. Consequently we see heremore distinctly than in any otherplace the influence of the calcite onthe formation of the crystals. Combination: è{oio}, rl^O},^{l40}, s{t20}, ?{?
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectgeology, booksubjects
