{"product_id":"black-chert-nodule-polished-freeform-bicolor-collector-specimen-lapidary-display-1-11-kg","title":"Polished Black Chert Nodule Tan Chalcedony Cortex 1.11 kg — Lapidary Specimen Display Piece Collector","description":"\u003cp\u003eThis polished black chert nodule weighs 1.1 lbs (approximately 1.11 kg) and presents a striking natural contrast between its opaque jet-black chert interior and a warm, patterned chalcedony outer cortex banded in tan, cream, and grey. The color boundary zones are sharp and well-defined, giving the piece an almost sculptural quality.\u003c\/p\u003e\u003cp\u003eChert is a microcrystalline to cryptocrystalline silica rock formed in sedimentary environments. The chalcedony cortex — a fibrous variety of quartz — developed as silica-rich fluids migrated through the outer rind of the nodule over geological time. The result is a naturally occurring two-tone specimen that requires no enhancement beyond the polish itself.\u003c\/p\u003e\u003cp\u003eThe high-gloss lapidary polish was applied to maximize visual impact, pulling out the natural banding and luster of both the chert core and chalcedony skin. This finish makes the piece well-suited for display collections, lapidary study, or use as a reference specimen for understanding cortex formation in siliceous nodules.\u003c\/p\u003e\u003cp\u003eMid-grade collector specimen. One piece available. What you see is what you ship.\u003c\/p\u003e","brand":"garland_workshop","offers":[{"title":"Default Title","offer_id":56279977132324,"sku":"GWL-00256","price":84.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0867\/4875\/8308\/files\/GWL-00256_01.png?v=1789328951","url":"https:\/\/zebraindustries.net\/products\/black-chert-nodule-polished-freeform-bicolor-collector-specimen-lapidary-display-1-11-kg","provider":"Zebra \u0026 Co.","version":"1.0","type":"link"}