Smithsonite gemstone is of a zinc carbonate chemical composition. It occurs in a trigonal - rhombohedral crystal structure. It is often found as a secondary mineral in the oxidation zone of zinc ore deposits.

The color of smithsonite varies depending on the trace impurities found in the gemstone. It is often in different shades of light-blue to blue, light-green to green, pink, and or come mixed with green and blue turquoise hues. Copper gives Smithsonite its green and blue colors whereas Cobalt gives Smithsonite its pink and purple colors. Cadmium gives the yellow color in Smithsonite and Iron is responsible for the brown to reddish colors in Smithsonite. Moreover, Smithsonite gives a blue-white, pink, brown fluorescence.

Smithsonite has a hardness of 5 on the Mohs scale and has a perfect cleavage. Smithsonites are transparent to opaque with a glass-like luster. In aggregate form, Smithsonite’s luster is typically pearly and it is often banded.

Smithsonite is an important ore of zinc and thus it is also known as ‘Zinc Spar.’

Smithsonite is usually found in globular or botryoidal (grape-like) aggregate form rather than in pure crystals. Therefore, as a gemstone quality crystal Smithsonite is extremely rare. It is primarily a gemstone for collectors.

Smithsonite and Hemimorphite are two of the zinc-bearing minerals, and for many years it was believed that these two minerals were one and the same. At first, these two minerals were grouped under the name of Calamine, and it was in 1803 that the British chemist and mineralogist, James Smithson described Calamine as two different minerals; one being Smithsonite, a zinc carbonate and the other Hemimorphite which is of a zinc silicate chemical composition. But it wasn't until 1832 that Francois Sulpice Beudant named the zinc carbonate ‘Smithsonite’ in honor of James Smithson.

Another difference between these two zinc-bearing minerals is their crystal structure. Smithsonite forms in a trigonal crystal structure, whereas Hemimorphite forms with orthorhombic crystals.

Hemimorphite has a hardness of 4.5 to 5 on the Mohs scale whereas Smithsonite has a hardness of 5. Smithsonite has a density of 4.4 - 4.5 which is higher than both Sapphire and Ruby. Nonetheless, Hemimorphite is rarer than Smithsonite.

Chrysoprase looks similar to Smithsonite. However, Smithsonite is softer and usually occurs in lighter colors than Chrysoprase. Chrysoprase has a hardness of 6-7 on the Mohs hardness scale.

To enhance its color and maximize its beautiful luster, Smithsonite is often cut en cabochon. It is also shaped into ovals and cushions, pears and marquise shapes.

Smithsonite is not typically treated or enhanced in any way. However, in globular or botryoidal (grape-like) aggregate form, it may be surface-oiled to enhance its luster.

Trade names of Smithsonite include:

Bonamite – the blue to green gemstone quality Smithsonite.

Dry bone ore – the porous smithsonite often found in a honeycomb shape.

Turkey fat ore – the botryoidal form of yellow smithsonite.

Cadmium smithsonite – the yellow to green smithsonite, colored by cadmium.

Copper smithsonite – the blue to green smithsonite, colored by traces of copper.

Other mineral associated with Smithsonite are Malachite and Azurite. Smithsonite can also pseudomorph into Calcite or Fluorite.

In the past, it was believed that smithsonite could help balance and heal the endocrine system and reproductive organs. It will clear and relieve one’s sinuses, regulate digestive disorders and ease alcoholism and osteoporosis.

Smithsonite exudes calm and resonates soothing energy. It helps the wearer relief tension and stress. It gives inner peace and tranquility. It harmonizes the emotional and mental body and connects the wearer to her inner self. It is also believed that Smithsonite encourages joy and compassion to oneself and others.

Smithsonite is associated with the zodiacal signs of Pisces and Virgo and also with the element of water. It is the planetary stone of Neptune.

Due to Smithsonite’s brittle tenacity and softness, not to mention its perfect cleavage, special care must be taken in order to prevent it from splitting, chipping and fracturing and scratching.

It is recommended that it be set in well-protected mountings. Cabochon Smithsonite rings should be worn only on special occasions as rings are more prone to knocks and scratches. It is better worn as earrings, pendants, pins or brooches.

Smithsonite is also porous which means that it can be stained from absorbing sweat or chemicals such as perfumes.

Avoid harsh chemicals such as bleach or sulfuric acid. Clean your gorgeous Smithsonite by simply using a soft cloth or brush with soap and water. Rinse well and make sure that all soapy residue has been removed from your Smithsonite gemstone.

Significant deposits of Smithsonite are found in Australia, Mexico, Namibia, Zambia, Italy, Greece, Spain and in the United States.