Every crystal varies slightly, and sometimes even drastically. Every one is unique.
Here is a reference, so you can know what sort of crystals I commonly use for my jewellery designs.
Pictured above is various raw and tumbled labradorite.
Below is a raw chunk of Labradorite in two different angles, under natural light.
At first glance it often appears a bland grey (left), but with the right perspective it flashes gorgeous colours (right).