What’s In The Box? A Light in the Dark

You’ll almost never see gorgeous red realgar crystals on display, and if you do, it won’t be for long. Why? It turns out that realgar is one of several minerals that changes and degrades when exposed to light.

Realgar crystal

Realgar from Shimen, Changde Prefecture, Hunan, China

If left on display, this light-sensitive crystal would begin to turn dark and eventually change into an entirely different mineral: the powdery orange pararealgar, shown below. This happens because of the energy carried in certain wavelengths of light. When that energy hits atoms in the crystal, it causes some of their atomic bonds to break and rearrange into a different structure. For this reason, realgar is one mineral that will always stay inside the box!

Pararealgar crystals

Pararealgar from Royal Reward Mine, King County, Washington, USA

Even common minerals like amethyst and fluorite can begin to fade over time, especially if exposed to bright sunlight for long periods. We recommend displaying your treasures on a shelf rather than a windowsill.

This post is part of our What’s in the Box? series.

Advertisements

One thought on “What’s In The Box? A Light in the Dark

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s