Lemon Chrysoprase or Citron Chrysoprase isn’t actually a Chrysoprase but is a yellow-green variety of Magnesite, found exclusively in the Eastern Goldfields area of Western Australia in a belt of ultramafic rocks that stretch from Norseman in the south to near Wiluna in the north.
It occurs in many of the same locations as that of chrysoprase, most notably Yerilla , Marshall Pool & Goongarrie but in numerous other places as well and is scientifically classified as a Magnesite.
It’s believed to have its trade name since it’s usually found in a Chrysoprase Mine.
It occurs as veins & plates but also commonly occurs in nodular form, quite often exceeding many tons in weight for a single nodule. Usually the interiors of these large nodules are of lighter colour & porous which makes them unsuitable for gem cutting.
Magnesite is magnesium carbonate and occurs as veins & nodules and is an alteration product of serpentine and other magnesium rich rock types. This is produced by hydrothermal leaching of the magnesium from the serpentine. Calcium, manganese, cobalt, and nickel may also occur in small amounts.
In Western Australia most magnesite is white, however in certain locations the presence of nickel mineralisation is responsible for the pleasing green colour found in "lemon chrysoprase".
Extra Fun Facts
The historical significance of Lemon Chrysoprase can be traced back to ancient times, with evidence of its use as a talismanic and healing stone dating back to the Middle Ages. This gemstone has been mentioned in various historical texts, including the Bible, where it is listed as the tenth foundation stone of the New Jerusalem in the Book of Revelations.
It is great reading these blogs. It allows us to read about the history and knowledge of the product. Thank you Dee for doing this. Gives me a better understanding of each one.