hard opaque white mineral in flat smooth layers of unusual shapes

Since the included minerals, liquids, and gases are well protected from chemical alteration, quartz inclusions open a window to the past to the scientist. The best example of a quartz with epigenetic inclusions is rose quartz. Very often these inclusions are specifically oriented with respect to the crystallographic axes of the main crystal.

When the conditions during crystal growth allowed the incorporation of elements into the crystal lattice that are incompatible with the crystal structure at different temperatures or pressures, these elements may separate from the lattice to form new minerals once the conditions change.

Minerals can get into another mineral by exsolution.Here the quartz crystal might have been partially encrusted by another mineral when growth halted transiently and continued later, such a case could be considered a syngenetical formation that got overgrown. Sometimes inclusions cause the formation of phantoms. Crystals may be distorted beyond recognition and a non-destructive identification may pose a real problem even for a mineralogist. The shape of the included minerals often deviates from the typical forms and habits that develop during unhindered growth. Quartz crystals and the included minerals grow simultaneously.Included fibers than run through the entire crystal at random orientations are typical examples. These inclusions are called protogenetic. The growing quartz crystals engulfs them and the original form of the included minerals is preserved. The minerals have formed before the quartz.

Hard opaque white mineral in flat smooth layers of unusual shapes