Willemite

From the fluorescent capital of the world, this is a rare specimen of well-developed Willemite crystals, partly-embedded in snow-white massive Calcite, itself exhibiting superb fluorescence.  I of course refer to the Franklin Mining District in Sussex County, New Jersey, USA, that unique zinc-rich orebody hosted in a wide syncline whose opposite outcropping ends gave rise to the Franklin and Stirling Hill mines.  This is a rare specimen because Willemite typically occurs as a massive ore at this locality and is seldom seen as good equant crystals.  Three good sized crystals have been exposed, ranging from 1.8 to 1.1 cm across, together with two minor crystals.  The Willemite forms caramel-brown dodecahedral crystals with lozenge-shaped faces and a waxy lustre.  Under LWUV these fluoresce beautiful chartreuse-green against a bright salmon-pink Calcite matrix, and under SWUV the Willemite becomes bright limey-leaf green and the Calcite hot-scarlet.  An excellent Franklin crystallised Willemite which any seasoned Franklin collector would be pleased to own.