An Australian Molybdenite Specimen. There is no matrix at all. Hard to find in this size. Molybdenite is the main ore of the metal molybdenum. A great addition to your metals collection. Some are using specimens like this Molybdenite Crystal as a power transistor by slight modification in the lab.
Kingsgate, NSW, Australia.
4.2cm x 4cm x 0.4cm, 11g.