Sapphire, for instance, is often pleochroic.

比如，蓝宝石常常具有性。

So pleochroic crystals seem to change color as you move your head, or rotate them in your hand.

所以当你动一动头，者在手中转动，具有性看上去在变换颜。

Not all non-cubic gems are pleochroic, and even when they are, the color change isn't always noticeable to our eyes.

并不是所有非等轴系宝石都具有性，并且即便它们具有这一性质，它们颜改变也不一定可见。