{"product_id":"jh-steward-dichroscope-c-1890-1910","title":"JH Steward Dichroscope (c.1890-1910)","description":"\u003cp\u003e\u003cspan\u003eThe dichroscope was a compact, low‑cost optical tool that made \u003cstrong\u003epleochroism\u003c\/strong\u003e visible at the jeweller’s bench, transforming early gemological identification. By splitting incoming light into two polarized rays, the device allowed observers to see adjacent colour fields in anisotropic gems, enabling rapid discrimination between isotropic and doubly refractive materials. This immediate visual evidence was crucial for identifying stones such as corundum, tourmaline, and tanzanite, and for distinguishing natural gems from synthetics and imitations at a time when laboratory spectrometers and polarizing microscopes were not widely available.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003ePractically, the dichroscope democratized diagnostic practice by putting a reliable optical test into the hands of jewellers, field gemologists, and students. Its portability and ease of use meant that accurate screening could be performed in markets, workshops, and classrooms, reducing misidentification and fraud and improving confidence in trade transactions. The instrument also guided lapidary decisions—helping cutters orient rough material to maximize desirable colour effects—so its impact extended from identification to the commercial and aesthetic outcomes of gem cutting.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cmeta charset=\"utf-8\"\u003e\u003cspan\u003eThis is a museum archives and no unit is available for sale at this moment. \u003c\/span\u003e\u003c\/p\u003e","brand":"Gems.studio","offers":[{"title":"Default Title","offer_id":52045992231232,"sku":null,"price":0.0,"currency_code":"CAD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0963\/0397\/2672\/files\/JHSteward_Dichroscope1.avif?v=1779813191","url":"https:\/\/gems.studio\/products\/jh-steward-dichroscope-c-1890-1910","provider":"Gems.studio","version":"1.0","type":"link"}