These gorgeous pieces of Window Selenite are nearly clear as glass. You can learn more about selenite in general here. Window Selenite (also called Selenite Windows) is thought to be even more powerful and especially good for cleansing and meditation. These pieces were mined in Utah, United States.
Piece A is 32g, is roughly 0.8-0.9 cm thick, and is 7.5 cm across its longest dimension.
Piece B is 46g, is roughly 0.6-0.7 cm thick, and is 13.5 cm across its longest dimension.
Piece C is 95g, is roughly 0.8-1 cm thick, and is 16 cm across its longest dimension.