What Is Ammolite?

Nautilus

When people see Ammolite for the first time, they often mistake it for other stones.  I am often asked if it is fire opal, fire agate, or a type of specialized glass.  I have to smile - because it does and can look similar to all those different items.

Ammolite Fossil

But Ammolite is none of these.  It is actually the fossilized shell of an ancient sea animal that lived back during the dinosaur times (75-130 million years ago) called ammonites.  These ancient sea creatures resembled today's nautilus, with the exception that today's nautilus have very plain shells, whereas the ammonites of old had very brightly colored shells (or they became very bright during the fossilization process).

Ammolite:  fossilized shell that is considered a precious gemstone (like pearls or amber).

Ammonite:  the sea animal that lived back with the dinosaurs that created the ammolite shell.  
 

There are three main types of ammonites that fossilized to create Ammolite:  disk-shaped ammonites Placenticeras meeki and Placenticeras intercalare, and (to a lesser degree) the cylindrical baculite, Baculites compressus. 

Ammonites were cephalopods, or squid-like creatures, that thrived in tropical seas from the upper Cretaceous period until becoming extinct along with the dinosaurs at the end of the Mesozoic era.

Western Interior Seaway

Although varies species of ammonites lived all over the world, and their fossils can be found everywhere, the specific species that give us Ammolite lived within the Cretaceous or Western Interior Seaway.  Millions of years later, that seaway is long gone, and erosion has brought these fossils up to the surface.

The largest deposits of Ammolite have been found in Canada.  But other smaller deposits have been found in Montana, Utah, and North Dakota.  A small company in Utah has filed a claim and surface mined generous supply of Ammolite.  You can visit their website to get USA Ammolite at much lower prices than that being sold from Canada.  www.UtahSeafireGems.com

Ammolite Quality

How do you know if what you are looking at is really a high quality Ammolite stone?

That's a great question!  Unlike other gemstones, Ammolite quality is not based on the 4 C's (color, clarity, cut, and carat/size).  Although there are some similarities.

Color characteristics:  it is important to know that one of the basic characteristics of Ammolite is that it can have what is called a chromatic shift of color as it is turned or tipped in the light.  Reds will change to greens, yellows to orange, and greens to blues and purples.  (In this way, it is very similar to looking at high grade / broad flash opal - where the colors change as the stone is tipped or turned.)

Another characteristic of this fossilized stone is that it can have a shattered look to it.  This is commonly called "dragon scales".  It is absolutely gorgeous!  But this is a matter of preference - some customers really like this look while others prefer the more solid look. 

Multiple Colors:  Although the colors can shift, a stone is more valuable if it shows multiple colors at a time (like bands or stripes of several colors).  However, I have discovered that this aspect of value greatly depends on the individual who is purchasing the piece.  While the standard of quality may say that multiple colors defines a higher quality stone, many people prefer a stone that is a solid single color.  Ruby red and emerald green stones seem to be the most popular single color stones.  (Customers also really like blues, but blue Ammolite is very rare in the Utah deposits, so very few of those have been sold.)

Amount of gemstone vs. host rock:  high quality stones have the Ammolite shell solid across the entire surface.  Lower quality stones have portions where the host rock shows through - so there are places where the bright Ammolite color is missing or absent.  One thing a few artists will do is use smaller pieces of Ammolite and create a mosaic of color on a host stone.  These can be absolutely beautiful pieces, but they are less valuable than a solid piece of Ammolite of the same size.  

Size:  As with other gemstones, the larger the piece of Ammolite the greater the value.  But again, this is tempered by the amount of gemstone vs. the host rock.

Being that Ammolite is a fossil, each piece is unique and if they are from the USA, they are also extremely rare.  But when making a purchasing decision, regardless of what the "rules" may say, the most important thing is that you buy something that you really like and enjoy! 

 Find out more at UtahSeafireGems.com.