Multicolored Birdseye Sphalerite Set, Balmat, NY

Here is a set of three different Birdseye Sphalerite pieces from the Zinc Corporation of America Mine #4 in Balmat, NY. This sphalerite formed as nodules. The fluorescent activator concentrations varied as the nodules were formed. This caused the nodule to be composed of alternating layers of fluorescing and non-fluorescing Sphalerite. When the rock was broken open, the nodules were split, revealing this beautiful Birdseye pattern. The activator type sometimes varied over time, so some of the Birdseye’s feature fluorescent color changes as well. This Sphalerite fluoresces best under Longwave UV and that is how the pictures were taken.

The upper left specimen features Red fluorescing Birdseye’s with thin yellow outlines. Some of the eyes go Red, Non-fluorescent, Red, and Yellow. Dimensions are 1.9" x 1.6" x 0.8", 2.3oz

The upper right specimen features Violet fluorescing Birdseye’s. Some of the eyes go Non-fluorescent, Violet, Red, Non-fluorescent. Dimensions are 1.5" x 1.3" x 0.7", 1.1oz

The Birdseye’s in the lower specimen are not as well formed but the colors are spectacular with Green, Yellow and Blue eyes. Dimensions are 2.2" x 0.9" x 0.5", 1oz

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