Crimson & Cobalt & Rose

Crimson is the Bohemian ruby glass — the deep vivid crimson of the most prestigious Bohemian colored glass type. Bohemian ruby glass: the specific deep vivid crimson-to-ruby of Bohemian gold ruby glass (Goldrubinglas — 'gold ruby glass' — produced by adding an extremely small amount of gold chloride — approximately 0.01-0.02% by weight — to a specific lead-potassium glass base, then reheating the initially colorless glass to a specific temperature range — approximately 600-700°C — the 'striking' temperature — at which the gold chloride reduces to colloidal gold nanoparticles of approximately 5-30 nanometers diameter — whose specific surface plasmon resonance absorbs green and blue light while transmitting the most deeply vivid red-to-ruby — the specific coloration being determined by the most precisely controlled particle size and particle distribution). History: Bohemian gold ruby glass was perfected in the late 17th century — specifically attributed to Johann Kunckel von Löwenstern (1637-1703 — the most important German alchemist and glass technologist of the 17th century — who served as court glassmaker to Elector Friedrich Wilhelm of Brandenburg in Potsdam — and who described the production of gold ruby glass in the most important glass technology treatise of the period: 'Ars vitraria experimentalis' — 1679 — the most comprehensively documented account of colored glass production in the 17th century). The Pfeiffer invention: the most technically significant 18th-century development in Bohemian ruby glass was the introduction of the 'copper ruby' (Kupferrubinglas — produced using copper oxide instead of gold chloride — a far less expensive colorant — allowing the most dramatic reduction in the cost of ruby glass production without significant sacrifice in the visual quality). Cobalt is the Bohemian cobalt glass — the medium vivid cobalt of Kobaltglas. Bohemian cobalt glass history: Bohemian cobalt glass (Kobaltglas — 'cobalt glass' — the most widely produced and most internationally traded of all Bohemian colored glass types — produced by adding cobalt oxide — CoO — to the glass melt in concentrations of approximately 0.1-1.0% by weight — with lower concentrations producing lighter, more transparent cobalt blues and higher concentrations producing the most deeply saturated and most opaque dark cobalt blue) has been produced in Bohemia from at least the 14th century — when the cobalt mines of the Erzgebirge (Ore Mountains) first began supplying cobalt ore (smaltite — CoAs₂ — and erythrite — Co₃(AsO₄)₂·8H₂O — the most important cobalt mineral sources in the Bohemian mining tradition) for the glass furnaces of the Bohemian Forest and the Ore Mountain regions. The most important Bohemian cobalt glass centers: Nový Bor (formerly: Haida — Bohemian: Nový Bor — the most important north Bohemian glass-making city — producing the most widely exported and most commercially significant Bohemian cobalt glass), Jablonec nad Nisou (the most important Bohemian costume jewelry and glass bead manufacturing center — producing the most widely distributed Bohemian glass beads in the world), and Karlovy Vary (formerly: Carlsbad — the most important western Bohemian spa city — home to the most prestigious Bohemian luxury glass and porcelain production). Rose is the uranium opaline — the vivid electric rose of Bohemian uranium opaline glass. Uranium glass history: uranium glass (also called vaseline glass — for its characteristic petroleum-jelly-like yellow-green color in daylight — or custard glass) was first produced in Bohemia in the 1830s — specifically attributed to Josef Riedel (the most important Bohemian glass manufacturer of the early 19th century — founder of the Riedel glass dynasty — whose descendants continue to operate as one of the most important luxury glass manufacturers in the world — Riedel Crystal of Kufstein, Austria) who named two specific uranium glass colors 'Annagrün' (Anna green — a yellow-green uranium glass) and 'Annagelb' (Anna yellow — a yellow uranium glass) after his wife Anna Maria. The uranium fluorescence: uranium glass fluoresces vivid yellow-to-green under ultraviolet light — with the specific fluorescence color being one of the most dramatically vivid and most immediately shocking fluorescent phenomena in the natural world — the yellow-green fluorescing characteristic of uranium glass becoming one of the most distinctive and most immediately identifiable properties of the material. When uranium is added to an opaline glass base (a glass containing a substantial proportion of tin oxide, bone ash, or fluorspar — which produces a semi-transparent to opaque milky glass) rather than to a transparent glass, the resulting uranium opaline can appear pink to rose-to-electric-rose in daylight — the specific effect depending on the precise balance of uranium oxide, opacifying agents, and other colorants.