The Jeffrey Asbestos Mine, located in the town of Val-des-Sources, Quebec, has also been a prolific producer of a variety gems and fine minerals specimens.  Although, asbestos production began in 1881, mineral collectors have only known about the presence of mineral specimens and gems since about 1950.  Grossular garnet from the Jeffrey Mine occurs in colours ranging from pale pink to orange/pink, light yellow, colourless and the colour varieties hessonite (orange to orange/brown) and tsavorite (yellowish green to bright vivid green).  Hessonite is by far the most abundant colour variety and helps make the Jeffrey Mine one of Canada's most important and certainly most prolific gemstone localities.

One of the rarer colours in grossular is colourless and near colourless.  The garnets offered for sale on this page are mostly colourless.