{"title":"Ankerite","description":"\u003cp\u003e\u003cstrong\u003eAnkerite\u003c\/strong\u003e is an iron-rich carbonate of the \u003cstrong\u003edolomite group\u003c\/strong\u003e, forming a solid-solution series with \u003cstrong\u003edolomite\u003c\/strong\u003e and \u003cstrong\u003ekutnohorite\u003c\/strong\u003e as iron substitutes for magnesium in the crystal structure. Its signature curved, saddle-shaped rhombohedra and warm rusty-brown to orange color, caused by surface oxidation of iron, make it instantly recognizable among carbonate specimens, distinguishing it from paler dolomite and calcite.\u003c\/p\u003e\u003cp\u003eThe species takes its name from Styria, Austria, home to the classic \u003cstrong\u003eErzberg\u003c\/strong\u003e deposit at Eisenerz, where sharp ankerite rhombs are found beautifully associated with clear \u003cstrong\u003equartz\u003c\/strong\u003e. Other important localities include the \u003cstrong\u003eHomestake Mine\u003c\/strong\u003e in South Dakota, the \u003cstrong\u003eTui Mine\u003c\/strong\u003e in New Zealand, the \u003cstrong\u003eMesabi Range\u003c\/strong\u003e banded iron formations of Minnesota, and the \u003cstrong\u003ePrego Mine\u003c\/strong\u003e at Kladno in the Czech Republic, where ankerite occurs with \u003cstrong\u003esphalerite\u003c\/strong\u003e and \u003cstrong\u003edickite\u003c\/strong\u003e. It is also a widespread gangue mineral in hydrothermal veins carrying \u003cstrong\u003egalena\u003c\/strong\u003e, \u003cstrong\u003epyrrhotite\u003c\/strong\u003e and \u003cstrong\u003echalcopyrite\u003c\/strong\u003e, and accumulates in low-grade metamorphosed ironstones and iron carbonatites.\u003c\/p\u003e\u003cp\u003eCollectors seek ankerite for its well-formed rhombohedral habit, attractive iron-oxide coloring, and its role in illustrating the compositional bridge between calcite and dolomite. Fine matrix pieces with contrasting sulfide or quartz associations are especially prized, making authentic, well-labeled ankerite specimens a worthwhile addition for carbonate and systematic mineral collections.\u003c\/p\u003e","products":[],"url":"https:\/\/www.italmineral.com\/collections\/ankerite.oembed","provider":"ITALMINERAL","version":"1.0","type":"link"}