Fossil ammonite shell itself is quite thin and unstable, so to be used in jewelry it needs to be stabilized with epoxy and affixed to a backing to create what is known as a doublet. This lacks the vibrant color and shell thickness that is needed to produce suitable gemstones.Īmmolite is a relative newcomer to the gemstone and jewelry scene having first appeared on the market in the late 1960’s. While iridescent ammonite fossils have been found in many locations including Madagascar, Utah and Russia the quality is far below what would be considered ammolite. If the mining process wasn’t narrow enough, the overall amount of ammolite collected is rapidly declining, contributing to ammolite mining’s uncertain future. It is not environmentally or economically feasible to search like this, so mineralogists suspect that ammolite mines don’t have much more of a future. ![]() This process is not broad enough to catch many pockets of ammolite and large-scale excavation is required to locate the ammolite. When mining for ammolite, drilling and coring to search for this mineral is out of the question. In addition to the lack of global availability, the process in which ammolite is exhumed is limited by a multitude of factors. Because of this scarce availability and the flashiness of the mineral, the ammolite has become a prized collector’s piece. Most of the ammolite in the world is pulled from the Bearpaw Formation in Alberta, Canada. They even go so far as to re-seed that patch of moved earth with native grass seed. The depth needed to attain ammolite is not very deep, so when Korite is done exploring an area they will replace the dirt as it was excavated, layer by layer. Korite, the largest ammolite mining corporation, digs for ammolite with an environmentally conscious mindset. Experts suggest that an influx of marine sediment is responsible for the thicker, heavily fractured ammolite that comes out of the K Zone. Ammolite from the Blue Zone is typically hand collected in river valleys where large-scale mining equipment is either forbidden or unable to access. This phenomena will typically result in less fracturing of the ammolite shell but a reduced thickness when considering the lack of heavy concretion. A reference to the ammolite being accompanied by a thin layer of iron pyrite plating. ![]() The primary reason for this is the depth at which it is found in comparison to the Blue Zone.Īt a depth of about 65 meters the Blue Zone comprises what is often labeled as sheet material. Most of the ammolite on the market is from the K Zone. This layer is referred to as crush material because of the state of the ammolite after millions of years of sediment compacting and deposition. The K Zone is much closer to the surface, about 30 meters down and is characterized by thick concretions that envelop the ammolite. These layers are separated by about 35 meters (about 115 feet) and have different geologic compositions. Open pit mining operations at one of Korite's ammolite mines in Alberta.Īmmolite is found in one of two stratigraphic layers of the Bearpaw Formation: the K Zone or the Blue Zone. Reds and greens are the most commonly seen colors, owing to the greater fragility of the finer layers responsible for the blues. The thicker the layers, the more reds and greens are produced the thinner the layers, the more blues and violets predominate. In the case of nacreous shells, the plates of aragonite that form them are stacked at a thickness that is similar to a wavelength of visible light that it is reflecting. Structural coloration is when there are minute variations in microscopic parallel structures on an object's (typically an animal’s shell, feathers, or wing cases) surface that break up the way light is refracted and reflected through the surface and to the viewer’s eye. Lamellar structures are not only strong and durable, but often create an opalescent or iridescent effect, by a process referred to as structural coloration. This means that the ammolite shell is composed of many fine alternating parallel layers and structures. Complete specimens of this quality are rare and prices run into the tens or even hundreds of thousands of dollars.Īmmolite’s iridescence is due to the lamellar structure of its nacreous shell. An ammonite composed entirely of ammolite.
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