Definition of dioptase in English:



  • A rare mineral occurring as emerald green or blue-green crystals. It consists of a hydrated silicate of copper.

    • ‘The Algomah mine is best known for lapidary material and copper-bearing microminerals, including (but not limited to) plancheite, kinoite, dioptase, azurite, and atacamite.’
    • ‘Tantara dioptase occurs well crystallized with quartz, plancheite, shattuckite, fornacite, and chrysocolla.’
    • ‘A good example of this potential for confusion is illustrated in specimen CM7075, dioptase, most probably from the type locality for the species in Altyn-Tube, Qaraghandy Oblys, Kazakhstan.’
    • ‘Dioptase is a very beautiful mineral and it is one of the few minerals that can challenge the peerlessness of emerald's deep green.’
    • ‘The color of dioptase does not photograph well and must be seen in person to appreciate.’
    • ‘The mine is well known for the rare secondary copper minerals that occur in the lode, including paramelaconite, cuprite, malachite, and dioptase.’
    • ‘Other Bisbee occurrences include the Shattuck shaft where it occurred in fibrous crystals to 5 cm associated with dioptase and the Southwest mine where thick crusts of parallel acicular crystals to 90 cm across were found.’
    • ‘Additional details of its history and mineralogy can be found in a Rocks & Minerals article published in concurrence with the 1985 Tucson Show, at which dioptase was the featured mineral.’
    • ‘For digital photography, SoLux bulbs are perfect, yielding accurate rendition of difficult-to-photograph minerals such as dioptase and azurite.’
    • ‘A number of lots of very fine dioptase had recently come to America from this locality.’
    • ‘Many of the best Tsumeb cerussite, dioptase, azurite, smithsonite, and other specimens passed through his hands en route to some faraway collection.’
    • ‘We had traveled across twelve time zones and back in time at least fifty years to get dioptase at the source, but our timing was as poor as the specimens.’


Early 19th century: from French, formed irregularly from Greek dioptos ‘transparent’.