This insane swirl of fluorescent colors is from the Sterling Mine, Sterling Hill, New Jersey. The unusual and interesting pattern of bright fluorescence is due to its hydrozincite, Willemite and calcite content. Under short wave UV the hydrozincite fluoresces bright blue, the willemite green, and the calcite shows a typical red response. The willemite is also phosphorescent after short wave UV. The size of this specimen is 8.2 x 5.9 x 4.5 cm, and it weighs 414 grams.
Shown above under short wave UV (254 nm), this technicolor rock features willemite (green), calcite (red/orange) and hydrozincite (blue).
After exposure to short wave UV, the willemite shows bright and lasting phosphorescence.
In the above photograph, the specimen is shown under visible light.