I considerate a privilege to find and handle very rare gemstones like the one pictured here. The stone at the bottom is a piece of natural untreated quartz. It has sections of pure clear quartz crystal and distinct areas of bright deep purple quartz, more commonly known as Amethyst. It also exhibits noticeable Phantom line visible through the Amethyst section. In addition there are distinct silver colored Goethite needle like mineral inclusions in the quartz. Overall this 5 sided quartz specimen makes for a one of a kind piece of natural beauty. The quartz is in a simple Platinum frame hinged to an 8 diamond Platinum top. The quartz is cut flat on the top and bottom. The Goethite minerals runs through the quartz and do come to the surface of the stone. Excellent condition, no repairs or defects. This looks great on the neck. 8 round diamonds approx. total weight .25cts. 1 fancy slice of rutilated Amethyst 16.31cts. Tested: Platinum. 10.5 grams. 1 7/8 x 1 3/16 inches.