| Sample # |
1 |
| Mineral
Name |
PLAGIOCLASE |
| Chemical Composition |
NaAlSi3O8 CaAl2Si2O8 |
| Luster |
Vitreous,
pearly on cleavage |
| Color(s) |
Usually white to off-white or dark grey |
| Streak Color |
White |
| Specifc Gravity |
2.6-2.8 |
| Habit |
Prismatic,
tabular, massive |
| Cleavage/Fracture |
2 good/ uneven |
| Hardness |
6 |
| Diagnostic Feature(s) | Twin lamellae (striations on crystal faces), hardness, luster |
