As a halite crystal is growing, new atoms can very easily attach to the parts of the surface with rough atomicscale structure and many dangling these parts of the crystal grow out very quickly (orange arrows). Eventually, the whole surface consists of smooth, stable faces, where new atoms cannot as easily attach themselves.
الكالسيت: Buy Loose الكالسيت at Wholesale Prices من عند ... الكالسيت. Calcite is a carbonate mineral and is the most stable form of calcium carbonate. With a hardness of only 3 on the Mohs scale, it can only be used in jewelry that won't be subject to knocks or scratches, such as earrings and pendants.