Minerals
(From left to right, as viewed in window 4. of cabinet B)
Adamite from Mexico; Franklinite and Willemite from New Jersey, USA; Manganocalcite from Peru In all three of these rocks, ultraviolet light reacts with chemicals within the minerals, causing them to fluoresce. In Adamite, which is chemically zinc arsenate hydroxide, trace amounts of copper and uranium give a greenish appearance and the fluorescent qualities. The second rock is a combination of Franklinite (zinc, iron, and manganese oxide) and Willemite ( zinc silicate), two minerals that commonly form together and are found at Franklin, New Jersey. These deposits are considered by geologists to be some of the most wondrous and unique ever discovered, with the dull black and brown grains transforming into an array of green fluorescents under ultraviolet light. The right hand mineral, Manganocalcite (manganese and calcium carbonates), has been polished into a smooth lozenge and appears a milk pink colour under white light but transforms into a bright pink fluorescent orb under ultraviolet light.
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