It has long been known from the emerald and chrysoberyl mine on the Takovaya stream, near Yekaterinburg in the Urals of Russia, where large crystals occur in mica-schist.

It is also found with topaz and amazonite in the granite of the Ilmen Mountains in the southern Urals and of the Pikes Peak region in Colorado, US.

[8][9] Small, gem grade individual crystals of phenakite showing a prismatic habit are noted in beryl dissolution cavities at the Noumas II Pegmatite, part of the Orange River pegmatite belt in the Northern Cape of South Africa.

[5] For gem purposes the stone is cut in the brilliant form, of which there are two fine examples, weighing 34 and 43 carats (6.8 and 8.6 g), in the British Museum.

The indices of refraction are higher than those of quartz, beryl or topaz; a faceted phenakite is consequently rather brilliant and may sometimes be mistaken for diamond.