Mineral properties hardness (scratch test) color luster special properties calcite 3 scratched by nail white dull/glassy bubbles with acid feldspar 6 scratches glass pink or white dull/pearly mica 2 scratched by fingernail black/gray shiny splits into thin sheets talc 1 easily scratched by fingernail white dull gypsum 2 scratched by fingernail white/gray dull quartz 7 scratches glass various colors glassy most common mineral fluorite 4 various colors can be banded or striped; multicolored q: a: you and your science group have been handed five mineral samples to identify. first, you sort the minerals by color. one has many colors. the group decides that it is either fluorite or quartz. what other property would you identify the mineral? a) luster b) hardness c) acid test reactivate d) crystal structure