{"title":"Beta Quartz","description":"\u003cp\u003e\u003cstrong\u003eBeta quartz\u003c\/strong\u003e is the collector's name for one of the most curious oddities in the silica family: crystals that grew as the high-temperature hexagonal polymorph of quartz, stable only above 573°C, and then inverted to ordinary trigonal \u003cstrong\u003ealpha quartz\u003c\/strong\u003e on cooling while preserving the original outer shape. Mineralogically it is not a separate species but a \u003cstrong\u003eparamorph\u003c\/strong\u003e after \u003cstrong\u003equartz-beta\u003c\/strong\u003e, meaning the chemistry (SiO2) and outward form stayed the same while the internal atomic symmetry silently dropped from hexagonal to trigonal during cooling. This makes true beta quartz impossible to find at room temperature, yet the pseudomorphs after it are eagerly collected precisely because they fossilize a fleeting high-temperature moment in a rock's history. The diagnostic habit is a stubby, double-terminated \u003cstrong\u003ebipyramidal\u003c\/strong\u003e crystal - sometimes called the \"Cumberland habit\" - built from two hexagonal pyramids with no prism faces, giving the characteristic barrel- or octahedron-like shape quite unlike the elongated prisms of ordinary rock crystal.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eBeta quartz\u003c\/strong\u003e forms almost exclusively in silica-rich volcanic rocks such as \u003cstrong\u003erhyolite\u003c\/strong\u003e, either as dull gray crystals embedded directly in the matrix or, more rarely, as loose crystals grown freely in gas cavities. The classic commercial source is the \u003cstrong\u003eSukabumi Regency\u003c\/strong\u003e of \u003cstrong\u003eWest Java, Indonesia\u003c\/strong\u003e, which supplies most of the gemmy, smoky-gray to golden bipyramids seen in mineral shops worldwide. In Europe, the \u003cstrong\u003eColli Euganei\u003c\/strong\u003e hills near Padova in Northern Italy are famous for amethyst-colored, barrel-shaped hexagonal beta quartz found in volcanic vugs, while historic German material comes from the \u003cstrong\u003eGrosser Auerberg\u003c\/strong\u003e near Stolberg. Additional rhyolite-hosted occurrences are documented across volcanic terranes in Mexico and the western United States, though gem-quality, well-terminated crystals remain scarce everywhere compared to ordinary quartz.\u003c\/p\u003e\u003cp\u003eCollectors prize beta quartz for its unmistakable geometric silhouette, its scientific interest as a record of magmatic temperature history, and its relative rarity compared to common quartz varieties like amethyst, citrine, or smoky quartz. Crystals are typically small, from a few millimeters to a couple of centimeters, translucent to gray or smoky in tone, occasionally with pits or matrix attachments that testify to rapid volcanic quenching; fully transparent, undamaged bipyramids command the highest interest. Because true beta quartz cannot be quenched or synthesized at ambient conditions, every genuine specimen offered as \"beta quartz\" is in fact this quartz-after-beta-quartz paramorph, making authentic, well-formed pieces a distinctive addition to any systematic silica-group or volcanic-mineral collection.\u003c\/p\u003e","products":[],"url":"https:\/\/www.italmineral.com\/collections\/beta-quartz.oembed","provider":"ITALMINERAL","version":"1.0","type":"link"}