Double terminated crystal on:
[Wikipedia]
[Google]
[Amazon]
A doubly terminated crystal (or double-terminated crystal) is a
A doubly terminated crystal (or double-terminated crystal) is a crystal
A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macr ...
with natural faces on both ends.
References
Crystals {{mineral-stub