Shell + Coral

SHELL

Pearls have intrigued humans for thousands of years. These mysterious and beautiful objects have a rich cultural history, they have funded business and industry, initiated conquest and exploration, adorned religious and secular art, and have been associated with royalty and celebrity.

Mollusks constitute one of the most diverse animal phyla on earth, with over 100,000 living species. They build the shells in which they live in, as well as pearls themselves. The shell and the pearls are made from the same material...

Aragonite ("ah-RAG-uh-nite") and conchiolin ("KON-kee-uh-lin") are the two materials the animal uses to build its shell. The mineral aragonite is arranged in sheets of flat six-sided crystals. Between each sheet, the mollusk secretes a very thin layer of the membrane-forming conchiolin. This composite material is called nacre ("NAY-ker") or mother-of-pearl. The crystalline structure of nacre reflects light in a unique way. One of the most distinctive features of nacre is the way it seems to glow from within. This property, known as "luster," gives pearl its unusual beauty. Luster results from the reflection of light rays not only off the surface, but also off the inner layers of nacre. The multiple layers of nacre also gives rise to the iridescence and orientation. The layers of nacre act like tiny prisms, refracting light so that it appears as all the colors of the rainbow. Pearls occur naturally in a spectacular array of colors, ranging from white to gold, purple and black. A pearls color depends on both the species of mollusk that produced the pearl and the environment in which the animal lived. In general, crystals of aragonite are white or colorless. The natural color of pearl is mostly due to conchiolin, which contains organic pigments.

Mother-of-Pearl comes from the South Pacific (Indonesia, Philippines, Tahiti, Australia, etc...) Much of the material comes from farmed shells, but a large percentage of Mother Of Pearl does in fact grow naturally in its natural habitat, and until the 20th century, divers in these regions spent most of their time hunting for mother-of-pearl rather than pearls. All material is hand cut and trimmed from the shell and carefully selected for pattern and color.

Gold-lip Pearl is scientifically the same as "white" Mother-of-Pearl, only that gold is taken from the reverse side of the shell. Good quality dark gold shells come from the waters surrounding the Philippines and parts of Indonesia. Gold-lip shells will yield both gold pieces as well as colorful white pieces from the inside of the shell, though it is not desirable to have both colors showing on the surface of any one piece. Gold lip is priced based on depth of color and iridescence.

Black-lip Pearl is probably one of the most exclusive pearls in demand in today's knife and musical instrument market. It comes from small shells found in French Polynesia around Tahiti and its Archipelagos. Just under the the exterior bark of the shell is where the real beauty of the Black-lip shell lies. Like Gold-lip, Black-lip has a black/grey color around the lip of the shell. Also like Gold-lip, Black-lip is priced by the depth of color and iridescence. A nice pair of Black -ip will have every color of the rainbow in its iridescent black background. A pair is considered large if it has a usable area of 2 1/2" x 7/8' x .080". Currently, Black-lip is at an all time low with regards to availability.

Red Abalone is a very exclusive material that has a demand much greater than its supply. The Red Abalone shell comes from just off the Northern California / Southern Oregon coast. Its name is a bit deceiving, it isn't red at all, but gets its name from the exterior bark which has a very red or pink tint. Most shells are not large enough to yield realistic knife handles. This, combined with their tendency to be full of holes created by boring sponges, makes for only about 2% of all abalone harvested worth using. Abalone has two areas that are of particular interest to knife makers. First, there is the lip section which has a bulls-eye type pattern where iridescent pools of color blend together in a random larger pattern. Second, the heart section has a tight pattern of different colors and reveals the illusion of depth on the surface. Other Abalones include Blue- Green Paua from New Zealand, Awabi from Japan, and Green abalone from Mexico and Southern California. Most of these rarely get large enough to make a full exposed handle, and are primarily used for inlays.

FOSSIL CORAL

It is important to understand "fossil coral" is a natural stone formed from ancient corals. It should not be mistaken for protected and endangered coral reef from the modern oceans of today. Fossil coral is a natural stone that is formed when ancient coral is gradually replaced with agate. The proper name for this material is agatized coral or agatized fossil coral. Agate, also known as chalcedony, is a type of cryptocrystalline quartz or silicon dioxide. Under unique geological conditions, prehistoric corals and mollusks can fossilize by being replaced with agate from silica-rich ground water percolating through limestone. The fossilized coral typically appears as small flower-like patterns in the stone.

Agatized fossil coral can exhibit a wide range of natural colors, ranging from white and pink to brown, gray, black, yellow and red. Corals may vary widely within a single stone depending on weathering and oxidation and the original mineral content.

Corals are among the most colorful animals in the sea. Most corals live in warm, shallow, tropical seas and feed on plankton. The oldest fossil corals are from the Ordovican period, over 450 million years ago. Corals are marine animals with a sac-like body, mouth, tentacles and skeleton. It is the skeleton that survives in the fossil record. Corals may be solitary or found in large colonies.

In some cases corals were buried in sediment as crustal plate movements affected the land surface and as the oceans rose and fell. Temperature and pressure from compaction during burial resulted in those deposits becoming rock and part of the present day geological record.

Of the varieties of fossilized corals found throughout the world, exquisitely detailed specimens from the mountains of Indonesia are among the most unique. In Indonesia, entire coral heads are often completely preserved and appear just as they did 20 million years ago, although their density is much changed by replacement with silica, iron, manganese and other minerals. There are fern corals, brain corals, hex corals, honeycomb corals and many more.

For many years, ancient coral deposits have been mined for their high quality calcium, potassium, magnesium and sodium content which are used in health supplements. Fossil corals have been used for centuries in such other diverse places as fertilizers, building materials, and in filters to remove impurities such as chlorine and formaldehyde from water.

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