Ankerite with Sphalerite

specimen number:
2282111

location:
Nenthead, Alston Moor, Cumbria, England, UK

description:
Bladed crystals of ankerite in a cluster with lustrous black sphalerite crystals. In good condition. Naturally crystallized all around with no points of attachment.

The Nenthead mining complex, located near Alston in Cumbria, England, is a major historical extraction site within the Alston Block of the North Pennines Orefield. Geologically, the area comprises Carboniferous sedimentary rocks deposited in repetitive sequences known as cyclothems, with the thick Great Limestone acting as the primary host for stratabound replacement deposits and mineralized fissure veins. Hydrothermal fluids deposited sulfide ores throughout these formations, primarily yielding galena for lead extraction and sphalerite for zinc, along with accessory fluorite, barite, and quartz. Organized mining expanded rapidly following the discovery of the Rampgill Vein in 1690, with the Quaker-led London Lead Company dominating local operations throughout the eighteenth and nineteenth centuries until surrendering its leases in 1882. Ownership subsequently passed to the Nenthead and Tynedale Company and later the Belgian Vieille Montagne Zinc Company in 1896, which shifted the operational focus to industrial zinc extraction until underground production permanently ceased in 1961, followed by localized surface reworking of waste tips for fluorspar until 1971.

Questions about this specimen?
Send an email or call us: 314-341-1811.