Authentic Occurrence " It's OK to become attached! " tm

GEMOLOGY 101

Welcome! I have been asked to create a learning library of sorts for educational purposes. I decided to create this page to represent a gemstone each month.

There is a vast array of resources available to expand upon the representation here. In the future, I will be adding more items such as fossils, megalodon ( pre-historic shark's teeth ) and mineral specimens.

If you have a "thirst for knowledge" .....

Please bookmark the page and visit it often!

For previously featured specimens please visit the Library

Fossils:

Orthoceras

Goniatites were an early form of curved cephalopd. They are part of the ammonite family. The suture pattern has a zig zag appearance that is very distinctive. Goniatites lived from the middle of the Devonian Period to the end of the Permian Period which closed out the Paleozoic Era

Ammonites were a type of cephalopod that appeared in the fossil record during the Devonian Era. They are related to squid and octopus. The nautilus is their closest living relative. The ammonite shell had sections, with the living animal occupying only the section of the shell closest to the head. As the soft-bodied ammonite got larger, it grew a new shell section and sealed off the old one with a layer called the septa. All ammonites became extinct 65 million years ago.

Carcharodon Megalodon

Carcharodon Megalodon was a giant shark that lived during the Miocene and Pliocene epochs of the Cenozoic Era, between 2 million and 16 million years ago. Little is known for sure about these giant predators because all that remains of their existence are fossilized teeth. But what teeth they are! These giant shark teeth range in size from 3 inches long to 7 inches long. They are massive things that can be bigger than a man’s hand. It sets the imagination reeling. To put this in perspective a large great white shark measures about 20 feet long and weighs a little over 2 tons. A tooth from a shark like this is about 1.5 inches long.

The fossilized teeth are all that remains of this monster because sharks do not have bones. Their skeleton is made up of cartilage. This is what your ears and nose are made from. Cartilage does not fossilize well.

The white shark is its closest living relative. This is well accepted but sets the stage for debate over the family tree

Wildlife Conservation:

Safari Todd:

Director Of Education and Entertainment at Jungle Adventures

in Christmas Florida.

Follow him on twitter:

twitter.com/SafariTodd

June - Pearl

Pronounced

Purl

Pearls are the only gems that are grown inside living creatures, so rather than being mined like other gems, pearls are farmed and harvested. Pearls have been harvested from mollusks for thousands of years, either by chance or, more recently, purposely through culturing. From the start of mankind's love affair with them, pearls have been symbolic of class, purity, refinement, and wealth, but modern designs with fashionable new pearl shapes and colors are helping pearls appeal to a broader audience. They truly are not just your grandmother's pearls anymore.

Name Origin and Meaning

Just as the original discovery of pearls is unknown, the origin of the name is also uncertain. The word "pearl" may derive from the Latin perna, a type of shell, or sphaerula, meaning "spherical." The names of various types of pearls are modified by a word that connotes where they are cultured (South Seas) or the type of oyster that grows them (Akoya), with one exception being keshi pearls. The word "keshi" is Japanese for "poppyseed," so named because of their generally small size.

Discovery and History

The first pearl discovery is an ancient mystery, though it was likely accidental and by a fisherman who was opening oysters or mussels for food. Freshwater pearling has been known in China since 1000 B.C., and while the Chinese were culturing blister pearls as far back as the 14th century, whole cultured pearls have only been available since the 1920s. Natural pearls have been harvested for hundreds and maybe even thousands of years. A natural pearl occurs only once in 15,000 mollusks. In addition to oysters (saltwater) and mussels (freshwater), other creatures occasionally produce pearls, like the very rare and expensive pale orange Melo Melo pearls from marine snails and beautiful pink conch pearls with unusual flame patterns. Other pearls include recently discovered non-nacreous brownish-purple scallop pearls and distinctively blue-green iridescent abalone pearls.

Value

While some folks may believe there is no such thing as an ugly pearl, the jewelry industry grades pearls with a variety of factors, many of which are unique to pearls and unlike the value factors for other colored gems. The Gemological Institute of America (GIA) grades pearls based on their seven pearl value factors: size, shape, color, luster, surface quality, nacre quality, and matching. Luster, or the light reflecting from a pearl's surface, is the most important factor of a pearl's value and beauty. Surface quality refers to the presence or absence of irregularities or blemishes and their size, number, location, and type. Nacre quality refers to the thickness and quality of nacre layering; if it's too thin, the pearl's nucleus will be visible, and poorly layered nacre can create a chalky appearance.