set of various calcite stones cutout on white

background brown calcite calcium carbonate close closeup collage collection crystal crystalline cut cutout gem gemstone geological geology glendonite green iceland ikaite isolated lime mangano manganoan manganocalcite manganokalzit mineral mineralogy natural out piece polished raw rock rough sample set silfurberg simbircite spar specimen stone translucent transparent tumbled tumbling unpolished various white yellow