Norbergite + diopside
A rare famous mineral form the old mines of Franklin , New Jersey.It glows yellow under the short wave UV light. Often associated like in this case with diopside who turns blue and sometimes calcite who turns red.
The composition of norbergite is: Mg3SiO4(F, OH)2 , a Magnesium Silicate Fluoride Hydroxide with hardness 6-6.5.Translucent .
Size: 13.3x9.4x6.9 mm.