Black QuartzBlack quartz, also called smoky quartz, is made when traces of aluminum in the silica crystal are irradiated. This prevents the atoms from absorbing light. These crystals vary from a smoky gray to abyssal black with intricate geometric patterns. Each sold separately, the crystal you receive may not be one depicted in the images. Length: 2. 25 in 3. 5 in Width: 1 in 2 in Height: . 6 in 1. 5 in Weight: 1. 8 oz 3. 9 oz