Opal vs. Ammolite | What’s the Difference?

When looking at the beautiful light play of Canadian Ammolite, one may be left thinking about other colored gemstones with similar rarity and iridescence, like Opal. Wondering how to tell them apart? KORITE has all the answers, from the differences in origins of these gemstones to how they get their deep, rich colors - and which may be right for your next jewellery purchase!

Gemstone Similarities

First of all, let’s start with the similarities between Opal and Ammolite gemstones. Both are beautiful and are used in stunning jewellery. Both have relatively common occurrences of a base stone offset by an extremely rare and valuable colored version. For opal, this is the difference between common white or milky rough opal and colorful, rare fire opal. For Ammolite, the difference lies in whether or not the gemstone material was formed on Ammonite fossils. The fossils themselves are found worldwide, but the layer of gemstone we know as Ammolite is only formed under very specific circumstances, and only in one place on planet earth - Alberta, Canada. 

Ancient Beginnings

Additionally, both of these gemstones have ancient origins. While it's difficult to determine, Opals are estimated to have formed in the earth around 90-100 millions years ago. Ammolite is a bit younger - but it’s still a deeply ancient formation, occurring 71 million years ago. However, the differences begin when we discuss how these gemstones were formed all those years ago. 

Delve into the Details

Opal is a form of hydrated silica, which occurs when deposits of silica mix with water and seep into deep cracks in the earth’s crust. Over many years, the water evaporates and leaves behind these silica deposits. The play of color in fire opals comes from the densely-packed lattice of tiny silica crystals interacting with light shining through them. This changing display of color is known as iridescence, and Ammolite also displays it prominently - although through a different formation. Ammolite gemstone material is formed in a layer atop 71 million year old Ammonite fossils, and this process is due to heat and tectonic pressure over millions of years in the ancient bed of the St. Mary’s river. 

There are a few other factors differentiating Opal and Ammolite gemstones. For one - unlike Opals, Ammolite is considered to be an 'organic gemstone', similar to nacreous substances like pearls and mother-of-pearl. Additionally, Opal is a gemstone revered for thousands of years - but Ammolite has only recently been heralded for the rarity and beauty it possesses, partly because it was only discovered in the 1960s! 

Finally, an interesting discinction between Opal and Ammolite is within the values placed upon colors within the play of light in each store. In the Ammolite world, red, orange & green are considered common colors and purples, pinks & blues are revered for their exceptional rarity - and as such, command a high price. For Opal, the purple/blue spectrum is seen as more common, and it is the orange and red tones which command higher value. 

Now that you know the differences between Opal and Ammolite gemstones, it's time to check out KORITE's magnificent selection of Ammolite jewellery, all made with 100% Canadian Ammolite. Now featuring the brand new Starlight collection!