Smoky Quartz is a grey and translucent variety of quartz. It ranges in clarity from almost complete transparency to a brownish-gray crystal that is almost opaque. Like other quartz gems, it is a silicon dioxide crystal. It was not commonly used in the ancient times, but it has recently become a popular gemstone used for jewelry.
Oligoclase is a rock-forming mineral belonging to the plagioclase feldspars. The Mohs hardness is 6-6.5 and the specific gravity is 2.64-2.66. In color it is usually white, with shades of grey, green, or red.