How to Compare Garnet & Carnelian

Both garnets and carnelians are most often reddish in color.

Although garnet and carnelian are both semi-precious gemstones available in similar colors, there are some major differences between the two stones. Unlike carnelian, garnet is also available in a rainbow of colors. However both stones have a similar hardness, streak and luster. Telling the two stones apart is an important step in determining the value of the gemstone.

Things You'll Need

• Microscope
• Small scale

Instructions

1. Place the stones under a microscope and look at each one closely. In a garnet, you will be able to see the crystals, and in a carnelian you will not. Garnets are formed by crystals out of a combination of the minerals calcium, magnesium, ferrous iron, manganese, aluminum, ferric iron, chromium or, in rare cases, titanium with silicon dioxide. Carnelian, on the other hand is a form of quartz comprised of silicon dioxide and hematite into crystals that are too small to be seen with a microscope.

2. Compare the clarity of each stone. A natural carnelian will be cloudy, while the clarity of the garnet is more transparent.

3. Weigh the pieces of carnelian and garnet. The specific gravity of the garnet is a four, while the specific gravity of the carnelian is 2.6. This means that with two equal-sized pieces of these stones, the garnet will weigh more.

4. Look at the color of the stones. While all carnelians are reds, browns and oranges, only most garnets are in this color scheme. Garnets are also available in a wide variety of colors from black to yellow or green.

5. Look at the stones to examine cuts vs. polishing. A carnelian gemstone is almost always simply polished, while garnets are cut into facets.

References

• All About Gemstones: Carnelian and Sard
• Gemstones - Garnet
• The Garnet Family