Finally got an esperite specimen from Franklin, New Jersey. And it’s both brightly fluorescent and a beauty in natural light.
The esperite glows yellow, willemite green, and calcite red. The dark black non-fluorescent franklinite provides a nice contrast.
I first saw Franklin esperite almost 60 years ago. Back then it was identified as calcium larsenite. It was prominently featured in Nature’s Hidden Rainbows, a book that I sacrificially purchased as a child. And lost in a flood while studying geology at college.
Never thought I’d actually get to hold an esperite specimen in my hands.
Franklin specimens appeal to me in three ways. First, they are unsurpassed as bright, multicolored fluorescent rocks which lights up my imagination. Then they contain unique mineral combinations and structure that appeals to my geologic mind. Finally, as an ore specimens, most contain higher specific gravity minerals that are hefty and feel good to hold.
The Eastern United States page contains more images and information about this specimen.