1.6" Iridescent Ammolite (Fossil Ammonite Shell) - Purples & Greens

Iridescent Ammolite (Fossil Ammonite Shell) - Purples & Greens #301644

This is a 1.6" wide section of brilliant, iridescent ammolite from the Bear Paw Shale of Alberta, Canada. It has wonderful green, purple and blue hues that shimmer differently depending on what angle the specimen is viewed from.

This specimen comes with a floating frame display case.

Ammolite is an opal-like gemstone found primarily in Alberta, Canada. It is a kind of fossilized shell from ammonites, which in turn are composed primarily of aragonite, the same mineral contained in nacre (mother-of-pearl). The shell's microstructures are often preserved. In 1981, ammolite was given official gemstone status by the World Jewellery Confederation (CIBJO).

An ammonite composed entirely of ammolite. Complete specimens of this quality are rare and prices run into the tens or even hundreds of thousands of dollars.

An iridescent opal-like play of color is shown in fine specimens, mostly in shades of green and red; howver, all the spectral colors can be seen. This iridescence is due to the aragonite's microstructure: unlike most other gems, whose colors come from light absorption, the iridescence in ammolite comes from interference with the light that rebounds from stacked layers of thin platelets that make up the aragonite. The thicker the layers, the more reds and greens are produced; the thinner the layers, the more blues and violets predominate. Blues and especially purples are the rarest colors, owing to the greater fragility of the finer layers responsible for these colors.