{"title":"Gypsum","description":"\u003cp\u003e\u003cstrong\u003eGypsum\u003c\/strong\u003e is a soft, widespread evaporite mineral composed of hydrous calcium sulfate (CaSO₄·2H₂O), forming in alkaline lake muds, salt flats, clay beds, evaporated seas, and caves. With a Mohs hardness of only 1.5–2, it is soft enough to scratch with a fingernail, yet its crystal habits are among the most varied and collectible in mineralogy. The species includes several classic varieties prized by collectors: \u003cstrong\u003eselenite\u003c\/strong\u003e, the clear, glassy, prismatic form; \u003cstrong\u003esatin spar\u003c\/strong\u003e, with its silky fibrous sheen; \u003cstrong\u003ealabaster\u003c\/strong\u003e, a fine-grained massive variety long used for carving; and the sculptural \u003cstrong\u003edesert rose\u003c\/strong\u003e, rosette clusters of bladed crystals studded with trapped sand grains. Pure gypsum is colorless to white, but iron oxides and clay impurities can tint specimens yellow, brown, red, orange, or gray.\u003c\/p\u003e\u003cp\u003eThe type locality for record-breaking gypsum is the \u003cstrong\u003eNaica Mine\u003c\/strong\u003e in Chihuahua, Mexico, where the legendary Cueva de los Cristales (Cave of the Crystals) yielded selenite blades reaching over 11 meters long and weighing up to 55 tons, grown over hundreds of thousands of years in a stable, near-58°C hydrothermal environment. Nearby \u003cstrong\u003eSanta Eulalia\u003c\/strong\u003e, also in Chihuahua, has produced outstanding transparent selenite crystals, while \u003cstrong\u003eSaltillo, Coahuila\u003c\/strong\u003e supplies much of the desert rose material reaching the mineral market. Beyond Mexico, \u003cstrong\u003eMorocco\u003c\/strong\u003e is a leading global source of selenite, mined near the Atlas Mountains and fashioned into towers, spheres, and lamps, as well as sand-embedded desert roses. Classic American localities include the \u003cstrong\u003eGreat Salt Plains of Oklahoma\u003c\/strong\u003e, famous for hourglass-included selenite and sand-crystal specimens, plus Ellsworth (Ohio), Hanksville (Utah), Lockport (New York), and the Mammoth Caves of Kentucky, known for curved gypsum flowers. Other notable occurrences span Algeria, Tunisia, Australia, Peru, Spain, England, Poland, Russia, and Canada's Red River Floodway near Winnipeg, which yields fine yellow crystals.\u003c\/p\u003e\u003cp\u003eCollectors seek gypsum for the extraordinary diversity within a single species — from water-clear selenite blades with sharp rhombic terminations and arrowhead twins, to chatoyant satin spar, to the geometric charm of desert roses. Gypsum frequently occurs alongside \u003cstrong\u003ecalcite\u003c\/strong\u003e, \u003cstrong\u003edolomite\u003c\/strong\u003e, \u003cstrong\u003elimestone\u003c\/strong\u003e, \u003cstrong\u003ehalite\u003c\/strong\u003e, and \u003cstrong\u003eanhydrite\u003c\/strong\u003e, into which it converts under dehydration and heat. Its combination of remarkable crystal size potential, worldwide distribution, striking transparency, and low cost of entry makes gypsum a favorite for both beginner and advanced mineral collections, offering specimens that range from delicate cave-grown flowers to museum-scale giant crystals.\u003c\/p\u003e","products":[{"product_id":"lz-desert-rose-tunisia-0","title":"DESERT ROSE – Large Sand Disk from the Grand Erg Desert, Tunisia","description":"\u003cp\u003eNatural flat Desert Rose from the Eastern Grand Erg Desert, Douz, Kebili, Tunisia. This specimen displays exceptional crystal formation, unique natural morphology and beautiful sandy tones typical of desert gypsum formations.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong data-start=\"339\" data-end=\"356\"\u003eMineral Data:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong data-start=\"357\" data-end=\"372\"\u003eDimensions:\u003c\/strong\u003e 125 x 120 x 63 mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong data-start=\"391\" data-end=\"402\"\u003eWeight:\u003c\/strong\u003e 342 g\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong data-start=\"409\" data-end=\"424\"\u003eProvenance:\u003c\/strong\u003e Eastern Grand Erg Desert, Douz, Kebili, Tunisia\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"ITALMINERAL","offers":[{"title":"Default Title","offer_id":44328386494573,"sku":null,"price":49.0,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0693\/8027\/6333\/files\/imgi_31_IMG20240207180132.jpg?v=1772664377"},{"product_id":"lz-gypsum-italy-54-0","title":"GYPSUM \"SWORD\" – Giant Natural Swallow-Tail Crystal (54.5 cm), Italy","description":"\u003cp\u003eExceptional natural Gypsum \"Sword\" crystal from the Fiorini Quarry, San Lazzaro di Savena, Bologna, Emilia-Romagna, Italy. A unique single crystal measuring over 54 cm, displaying the classic swallow-tail crystal habit, excellent transparency, brilliant luster and beautiful golden-yellow coloration. Historic 1960s discovery. \u003cbr\u003e\u003cbr\u003e\u003cstrong data-start=\"669\" data-end=\"686\"\u003eMineral Data:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong data-start=\"687\" data-end=\"702\"\u003eDimensions:\u003c\/strong\u003e 545 x 65 x 27 mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong data-start=\"720\" data-end=\"731\"\u003eWeight:\u003c\/strong\u003e 1721 g\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong data-start=\"739\" data-end=\"754\"\u003eProvenance:\u003c\/strong\u003e Fiorini Quarry, San Lazzaro di Savena, Metropolitan City of Bologna, Emilia-Romagna, Italy\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"ITALMINERAL","offers":[{"title":"Default Title","offer_id":45388928614509,"sku":null,"price":0.0,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0693\/8027\/6333\/files\/IMG20231029171737.jpg?v=1782597497"}],"url":"https:\/\/www.italmineral.com\/collections\/gypsum.oembed","provider":"ITALMINERAL","version":"1.0","type":"link"}