The Jonas Mine, near Itatiaia in the Conselheiro Pena district of Minas Gerais, Brazil, is one of the most celebrated tourmaline localities of the twentieth century. A single pocket struck there in 1978 produced a quantity of intensely saturated red and pink rubellite of a quality and size that has not been equalled by any subsequent Brazilian discovery.

The 1978 strike

The mine was operated by the Lima family. In late 1978 a pocket roughly five metres deep was opened in a coarse-grained granitic pegmatite. The pocket yielded a documented production of several tonnes of gem and near-gem rubellite tourmaline, including individual crystals over a metre in length and discrete gem-quality terminations weighing many kilograms. Faceted stones from the find regularly run from ten to over one hundred carats, with a reddish pink to deep raspberry red colour, often with the slight purplish modifier that distinguishes the best Jonas material from later Mozambican production.

Material and trade

Jonas rubellite is prized for three qualities: a saturation that holds up under incandescent light, a clarity that allows large stones to be cut without obvious inclusions, and a hue that sits on the red side of pink rather than the pink-with-orange seen in some other deposits. The find was so large that gemmological literature of the early 1980s, including Gems & Gemology, treated it as a trade-defining event. Stones are still routinely described in the secondary market as Jonas rubellites when they match the colour profile, although by now genuine first-pocket material is concentrated in private collections, museum holdings and a small group of high-end dealers.

Later workings

The mine continued to be worked through the 1980s and 1990s and produced further pockets, none of which matched the 1978 strike in either size or colour. By the early 2000s output had largely fallen to small parcels of mixed-grade tourmaline. Mozambican rubellite from the Alto Ligonha district has since taken much of the market for large red tourmalines, but the Jonas name retains a pricing premium for verifiable original-strike material.