This is a Hashupi quartz crystal of very high quality.

Hashupi  quartz crystals of high quality are a very rare type of Himalayan  crystals, the higher the quality the higher the difficulty to get them,  not only because of climate conditions and high altitudes, that makes  miners only extract them for a few months a year but also because  crystals of such high quality  have been very hard to find in the mines.

Optical  crystals are crystals that are water clear, we can easily see through  them and are also crystals that have reached a very high state of  evolution.
You can read more about the characteristics of this crystal and others in the section, "Crystal Characteristics".

This crystal comes from Hashupi mine,  in  Shigar Valley, Shigar District, Gilgit-Baltistan, Pakistan.