Museum Monday: Sulphur Crystals

By Claire Schmotzer

Sulphur Crystals

Sulphur is the tenth most common element by weight in the universe, and the fifth most common on Earth. It goes without saying that sulphur and sulphur-containing minerals are easy to find here in the Black Rock. We have a number of specimens on display at the Last Chance Outpost and visitor center.

Chemistry

Close up of a sulphur crystal

Sulphur has the chemical symbol S and atomic number 16. It is nonmetallic and multivalent. At room temperature, sulphur is a bright yellow, crystalline solid. Sulphur burns with a bright blue flame and melts into a red liquid. Pure sulphur crystals have no scent. However, organosulfur compounds give scent to skunk spray, grapefruit and garlic. Hydrogen sulfide smells like rotten eggs. Most sulphur on Earth is found in sulfide and sulfate minerals.

Mineralogy

Yellow sulphur coating on a mineral.

Most often, sulphur is a powdery yellow coating on rocks. Square shaped crystals are yellow to yellowish brown with a resinous or greasy lustre. There are more than 50 morphologies, and specimens often come from sedimentary rocks. It is too soft to use for jewelry. Mindat has more information.

Uses

Historical

Sulphur on stones outside the office.

People started mining sulphur in ancient times. The Egyptians, Greeks, and Chinese had sulphur based medicines. In Greece, sulphur was used to spray buildings for bugs and bleach cloth. Sulphur is an ingredient in early Chinese gunpowder recipes.

Alchemists in India and pre-Modern Europe used sulphur. Indians liked using it with mercury. Sulphur’s name in Sanskrit means “The Smelly.” In European alchemy, the symbol for sulphur is a cross with a triangle on top. Alchemists made treatments for skin diseases using sulphur.

Modern

Sulphur is often found on quartz, gypsum, and other stones.

Today, sulphur is important to many industries. Just like in the past, sulphur is used to make medicine. Examples include Sulfa drugs and Epsom salts. Additionally, agriculture relies on sulphur. It is an important fertilizer and kills fungi and insects too.

You might find sulphur in the food you eat. Sulphur dioxide is the main preservative in wine. Producers sometimes spray it on other foods to help keep them fresh. Make sure to wash your fresh food in case sulphur fertilizer is on it!

Sulphur like the pieces in our collection are clues for geologists at hydrothermal power plants. Hydrothermal power plants use hot water from under the ground to make energy. When companies look for new places to drill wells, sulphur helps them. Rocks with sulphur on them are a sign of hot springs and pockets of hot water underground.

The Sulphur Institute has more information on modern uses and regulations regarding this element. Don’t miss their infographics.

Sulphur in and around Black Rock

There’s sulphur in our area. Look for it on rocks surrounding your favorite hot spring. Or better yet, take a trip out to Sulphur, Nevada. The ghost town got its name because of a sulphur mine. The mine was very busy until the 1960s. Now only the foundations remain.

Sulphur is an amazing element with many uses. Because it is common in geothermal and seismically active areas, it’s no surprise that the National Conservation Area is a great place to search for sulphur crystals. Check out our rockhounding page and review safety tips for hot springs and abandoned mines before you head out on adventures.