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From Australian Gemmologist.. a recent news update..
http://www.australia...u/agnews03.html
ANTIPATHARIAN BLACK CORAL
Antipatharian or thorny black corals are solid keratinous corals that form flexible endoskeletons. Various species of coral that belong to:
Kingdom Animalia
Phylum Cnidaria (Coelenterata)
Class Anthozoa
Order Antipatharia
Suborder: Scleraxonia
Family Antipathidae, Leiopathidae, Schizopathidae, Myriopathidae
Species Antipathes grandis
Antipathes grandis
Of the 150 species of this coral have been formally identified, 8 genera are subject to international trade. Commonly harvested species include Antipathes grandis, Antipathes dichotoma, and various Cirrhipathes sp. Individual species of antipatharian black coral may be either branching (bushy, feathery, fan-shaped, or bottlebrush shaped), or wire-like without branches (wire or whip corals). The polyps are small (0.5-5 mm ) and have six non-retractable tentacles. Live colonies are usually white, yellow, orange, red or green. The brown to black endoskeleton of this coral is covered in tiny spines that can range in size from about 0.04 to 0.6 mm. The size, shape and density of these spines, along with the pattern of branching of the colony and the appearance of the polyps, are used to identify species in this group. Colonies may reach up to 1.8 m in height.
Antipatharians black corals are found worldwide, but are most common in the Indo-Pacific and Caribbean regions. They grow at a wide range of depths, from 1 - 6000 m, but most are found between 30 and 80 m. They tend to be associated with low light conditions, either in deep water, or in turbid or shaded areas of shallow water. Black corals are frequently found where there are strong currents.
All antipatharian black corals are colonial with a rigid, rod-like skeleton made of protein. There are no calcareous components in the skeleton, and unlike gorgonian corals there are no calcareous spines (spicules or sclerites) in the soft tissues. Individual colonies are either male or female and feed by capturing zooplankton from the water. Colonies are slow-growing and long-lived. They form an important habitat for other species and support unique communities of marine life.
These black corals have been used for centuries both for charms and as medicine. The skeletons of black corals are still highly prized and are used in jewellery or sold as curios. These species are mainly collected by divers but in some areas may be harvested by submersibles or with non-selective net dredges. A small aquarium trade in live specimens has also been reported. Black corals are valuable and are therefore subject to considerable collecting pressure. Populations are slow to recover because they grow slowly and take a long time to reach sexual maturity. Black coral may be globally threatened but data on status and trends are limited.
Antipatharian black corals are listed in Appendix II of the Convention on International Trade in Endangered Species (CITES) , therefore trade in this species is regulated. A valid CITES export permit from the country of origin is required to bring black coral or objects made from black coral, such as jewellery, into the 158 countries that have ratified the CITES convention. In addition to CITES the export of black coral is banned or restricted by a number of countries. Black coral collection in some locations such as Hawaii is carefully managed to ensure that collection is sustainable. Black corals have been traditionally difficult to study because they live in deep water, however, a research programme in Hawaii has been running since 1970. Submersible craft are now used to investigate the ecology and distribution of black coral species. Black corals may form part of the marine community in Marine Protected Areas or areas where management plans are in place to protect the coral community.
Identification
1. Black (organic) antipatharian or thorny coral is identified by:
2. Its tree-like structure in cross-section.
3. Observation of remnants of radial spines often visible when polished surfaces of
this black coral are examined in tangential illumination with magnification. White
light is transmitted through thin superficial layers of this coral to gives these
layers a waxy brownish red colour against which the presence of spines is
immediately obvious.
4. Noticing a ‘salty burnt hair’ aroma when a hot point is judiciously applied to the
surface of this coral.
5. Determining a specific gravity of 1.34/1.35 for the material.
Clive's note.. The beginning of this article confusingly refers to the species Antipathes grandis.. there are I believe over a 100 members of the same families many of which can used for carving.
Picture notes:
Pic 1. A selection of raw umimatsu of a deep water species found in the northern pacific.. notice that the material is semi fossilized.. not nice to be using recently "live" material that has been collected. Help protect our fragile world.
Pic 2. A cross section clearly showing the ring structure and outer fossilization
Pic 3. The inner material exposed.. this is where the truly beautiful material hides
Pic 4. Another piece
Pic 5. Pic 4's end view
Pic 6. A great deal of work needs to go into carefully developing (lots of technique) and exposing the materials potential. There's a piece where I begun that process.. on the lefthand side I've brought it to a high gross with some subtle areas of work simulating a rotting log effect.. early days yet, but looking good
and next to that
Pic 7..... the back of a piece of of mine work.. height 35mm.. not quite finished though yet.
... though I tend to pick up subject materials more than carvable things.
