I found a large rock (it measures 1 foot across) on my family farm in Manitoba, Canada. I’ve reached out to gemologists at the University of Manitoba for identification and they’ve confirmed it’s garnets in gneiss, as suspected.
I want to know how valuable this specimen is, or if it isn’t of value at all. I don’t know where to go from here. Further, I’m curious as to what businesses would be interested in possessing it, and possibly mining the stones out of it.
Honestly your main buying buying audience is going to be collectors. The value of it is really dependent on how big the pieces of Garnet are and how many their are.
Firstly, are the garnets large and transparent? Secondly, are they a light hue in a color that is not red. Red garnets are very plentiful and often too dark to be of any gem value.
I don’t want to dash your hopes but getting large eg 5 carat (1 gram) garnets out of gneiss unharmed is not easy unless the gneiss is rotten and weathered. If you have a stream or creek on the farm try looking in gravels there for loose alluvial garnets, or around weathered gneiss.
show a picture with a penny for scale… large gem quality garnets are rare. Garnets forming in metamorphic rocks are plentiful and very rarely of gem quality, those that are usually are very small… if the garnets are very large but are not of gem quality, those who would be interested would be rock collectors and not gem collectors. Did the gemologists at the university identify what kind of garnets they are… garnets are a solid solution of different cations, including end member iron, manganese, calcium, magnesium… the general formula is X3Y2 (Si04)3 the X position is filled by divalent cations, Fe (ferrous), Mn, Ca, Mg, while the Y position is filled by trivalent cations, Al, ferric iron, and Chromium… that gives rise to a welter of varietal names… the cations can be identified by XRF or mass spec… the latter is far to expensive to run… but they might know from the type locale without doing any tests.