What is Ammolite?
Ammolite is a rare and highly iridescent organic gemstone formed from the fossilized shells of ancient ammonites that lived approximately 70–75 million years ago during the Late Cretaceous period. Found primarily in southern Alberta, ammolite is recognized as one of the world’s rarest gemstones and was officially designated as a gemstone by the World Jewellery Confederation (CIBJO) in 1981.
Its vibrant flashes of color are created by microscopic layers of aragonite within the fossil shell structure, producing brilliant iridescence similar to opal but with its own distinct appearance and structure. Colors may include red, green, blue, gold, purple, and more rarely violet or pink. Each piece of ammolite is unique, making it highly valued by collectors, jewelers, artists, and gemstone enthusiasts worldwide.
Location
Commercial-grade ammolite is found almost exclusively within the Bearpaw Formation of southern Alberta, Canada, particularly along the eastern slopes of the Rocky Mountains. Smaller occurrences have been discovered elsewhere, but Alberta remains the world’s primary and most significant source of gem-quality ammolite.
Because of its limited geographic origin, ammolite is often referred to as “Canada’s Gemstone.”
Ammolite Grading
Ammolite is graded based on several factors, including:
- Color range and intensity
- Brightness and iridescence
- Pattern and visual appeal
- Surface condition and cracking
- Coverage of color across the stone
- Rarity of colors displayed
Common Commercial Grades
AAA Grade
Exceptional brightness, vivid colors, strong iridescence, and a nearly flawless overall appearance.
AA Grade
High-quality color and brightness, attractive patterns, and strong visual appeal throughout all gem.
A Grade
Visible iridescence, moderate brightness, balanced color shifts, and a pleasing appearance overall.
B Grade
Lower brightness or limited colors, commonly used in artistic, collector, or decorative pieces only.
Types of Ammolite
Natural Ammolite
A naturally exposed ammolite surface with minimal alteration beyond cutting and polishing.
Doublets
A thin layer of ammolite attached to a backing material for added strength and stability. Common backing materials may include shale, synthetic materials, or other supportive substrates.
Triplets
Ammolite assembled with both a backing and a clear protective cap, commonly quartz, spinel, or glass, to improve durability and enhance visual depth.
Composite Ammolite
A broader term referring to assembled stones such as doublets and triplets.
Faced or Polished Ammolite
Stones that have been cut and polished into finished gem forms for jewelry or display.
Treatment Methods
Some ammolite may undergo treatments to improve durability, appearance, or stability. Common industry treatments include:
- Stabilization using clear resins or polymers
- Surface coatings to enhance durability and polish retention
- Backing reinforcement for thin material
- Protective caps used in triplets
Ethical disclosure of treatments is important within the gemstone industry, and CAGA encourages transparent representation of all treated or assembled materials.
How to Care for Ammolite
Ammolite is softer and more delicate than many traditional gemstones and should be handled with care.
Recommended Care
- Avoid harsh chemicals, cleaners, perfumes, and solvents
- Remove jewelry before heavy activity, sports, or manual labor
- Avoid prolonged exposure to direct heat or extreme temperature changes
- Clean gently using a soft damp cloth only
- Store separately from harder gemstones to avoid scratching
- Avoid ultrasonic cleaners or steam cleaning
Properly cared for, ammolite jewelry and specimens can remain vibrant and beautiful for generations.
Why Ammolite Is Special
Ammolite is not only a gemstone but also a rare natural connection to prehistoric life and Canada’s geological history. Its limited geographic source, extraordinary colors, and fossil origin make it unlike any other gemstone in the world. The is committed to helping preserve, educate, and promote this remarkable Canadian treasure for future generations.