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Black Coral

Some of you may have noticed my article in the August/Sept Lapidary
Journal about collecting black coral from So Florida’s beaches and
processing it into jewelry.

Due to space limitations, the LJ did not have enough room to include
about 5 pages of detail on what tools to use and how to smooth and
polish the coral. The three “projects” included in the Jewelry
Journal are but the tip of the iceberg of what can be done with the
coral. But to do many of the more complex things, requires the
knowledge of how to process it.

If any Orchid out there is interested in further or would
like to talk more about black coral, you can reach me off line at
@coralnut. I will provide the additional data at no
charge. Also, so you can try your hand at it, I have a limited supply
of coral available at a very reasonable prices.

Cheers from Don at The Charles Belle Studio where simple elegance IS
fine jewerly!

Hi Folks, Recently a singular nomadic acquaintance who wanders from
fair to fair and flea market to flea market showed me some black
coral. He praised it to the skies, its rarity, its value, its beauty
etc etc. But then, he’s one who would extoll the miracle working
properties of driveway gravel if he thought he could get away with it,
so I listened with mental reservation.

Then he told me that in the tropics where the stuff comes from the
locals heat it and bend it into bracelets etc. This surprised me:
coral was supposed to be aragonite, wasn’t it? (You can tell by now
that I know nothing about coral.) Wondering whether it might be
plastic I did the hot needle test - which yielded a chitinous odor of
burnt horsehair.

I looked it up in Walter Schumann: “Black coral” the entry said,
“conists of an organic hornlike substance.” OK, so that explained the
bending and the odour of burnt hair. But then the passage (in
"Gemstones of the World") went on to say that, “In the world
trade…it is of no economic importance.” I’m not sure what to make
of that. Does he mean black coral is so rare that it’s insignificant?
Or rather that it is so common?

Any insights as to the origins, rarity, value, legality, mode of
working, etc etc of black coral will be greatly appreciated.

Cheers & thanks,
Hans Durstling
Moncton, Canada

Well if black coral is so good then why don’t we hear more about it?
I have 6 sticks of the stuff abot 5" long , but like all organic
matter it seams to have a “load of it’s own”, none the less I still
enjoy looking at what I have until I hear more about it. Tom

Hi Hans: Check in with, aka “coralnut”. He knows
about all you need to know of black coral - I believe from Florida
based beds. He even two articles on Black Coral jewelry in two of the
last years Lapidary Journal issues.

Joe Bokor

Black coral has some value but it is not the be all and end all of
coral (or any other gemstone). I always liked the circular patterns
that showed up in it because I could create a circular wire design
around the piece that would mimic it. It is rare but it is not in
enough demand that the price should be very high for it. I think I
was actually given the pieces I have worked with (as opposed to buying
them) so they can’t be too valuable. I cannot believe that you can
heat and bend it but then I never tried that so who am I to say?

Daniel R. Spirer, G.G.
Spirer Somes Jewelers
1794 Massachusetts Ave
Cambridge, MA 02140

    Any insights as to the origins, rarity, value, legality, mode
of working, etc etc  of black coral will be greatly appreciated. 

Harvesting coral is illegal in some places. The world’s coral reefs
are pretty much endangered from rising ocean temperatures, and
tourists (both divers, snorkellers, and countries like Mexico
dynamiting the reefs to make passages for cruise ships).

I would think that ethically, it’s not good to work with this
material as it encourages further destruction and exploitation of

Even using coral that washes up on the beach can encourage demand,
and if demand is high enough, people will rip up the reefs to make a
few bucks.

  • darcy

Ah Hans, you have hit my favorite subject. I can talk for hours about
black coral but will try to be brief.

First, black coral is considered a ‘soft’ coral, meaning it is not
hard like the stony corals. (Won’t get into all the reasons behind
this and the taxicology and science which is very confusing). There
are a number of kinds of soft coral but black coral is an anomaly
because it isn’t really soft…it is, as you mentioned, a horny coral.
It is mostly protein and unlike stony corals in which the animal
itself becomes part of the structure as it dies, black coral is
actually the skeleton of the animal. The animal itself simply falls
off when it dies.

There are two types of black coral. Though both are made of the same
protein material they have some different physical attributes.
Antipatharian black coral is deep water (primarily below 100’) while
the Octocoral is shallow water primarily above 100’).

Antipatharian is the harder of the two though not necessarily more
dense (SG around 1.25). Once dried it cannot be re-wet (?) and formed
without great difficulty. It is more easily ground into cabochons or
carvings. In ancient times black coral was believed to protect one
from disease, hence the name - Antipatharian. Because it is from such
deep waters, it is difficult to obtain. It has been reported that in
1996 two divers died in Hawaii trying to get to deep water
Antipatharian coral. Thus, Antipatharian coral can be very very
expensive. It is found throughout the Pacific, around India,
Australia, the Red Sea, the Med and Caribbean.

Octocoral is softer (SG around 1.20). It is very plentiful around
South Florida and the Carribean, often found in piles washed up on the
beaches. After drying, it can be re-wet and tied into knots like
spagetti or bent into bracelets or earrings. It can also be bent by
heating it. Despite its availability, only a few people work with it
extensively and thus, it is still fairly expensive though nothing like
the Antipatharian.

Both types take a beautiful polish when worked properly but
Antipatharian is the more durable in that respect.


For more see the August 2000 edition of Lapidary
Journal. If you want more on how to work black coral,
contact me off-line at @coralnut. I will send you a six
page description of the process that didn’t get published in LJ due to
space constraints.

Cheers from Don at The Charles Belle Studio in SOFL where simple
elegance IS fine jewelry!

For considerable info on black coral check out this web sight Don has written
several articals on finding and the use of B-Coral hope this helps.

Many years ago I read an article about black coral and while in
Hawaii managed to get some down at the docks. A diver gave it to me
and told me it was good hard coral. He tod me most black coral grows
near the surface and is not very dense. Water pressure at greater
depths increases the density. Made sense to an Iowa farm boy- or
was I “fed a line”? Cary

Hi Hans, Like all things, the beauty and value of black coral is in
the mind of the beholder. Other than its looks, the value and
mystique of black coral is that 1) it is rarer than other corals, and
2) because in the United States harvesting is banned. (I dont know
if because of rarity or being endangered here). I have never seen
it twisted into bracelets. It is most commonly seen carved,
generally into forms of fish, i.e.: sharks, sting rays, dolphins etc.
I have noticed its modest among people whose hobby is fishing or have
a special fondness for all things of the ocean. I have seen "twigs"
of it mounted in gold to make earrings and pendants. Also in smaller
pieces (about 1 inch more or less) gold capped at the ends and
linked together to form a bracelet. In my travels I have seen it
enjoy more purchase power in the Caribbean Islands than anywhere
else. I have not seen it in shops here. Does this help?

Black coral is almost woodlike. It is fibrous and has growth rings
like a tree. It’s not that rare. It grows in the channels off the
Hawaiian Islands, around the Phillipines and Indonesia and probably
other Pacific Islands. The stuff around Hawaii is in deep water, 100+
feet and takes skilled diving to harvest. It has to be dried for
months before it can be cut. We wait a minimum of 6 months.

The thin branches can be soaked and bent. You can bandsaw the coral
and cut cabochons quite easily. You can shape it with files (dulls
them), grinding wheels, belt sanders, diamond burs, saws, assorted
steel burs, sanding discs, etc. You can progressively sand and then
polish or you can hit it with bobbing compound if you like. It
polishes to a shiny surface with yellow rouge.( Note: You can burn the
coral if you let too much friction build up. The burnt coral behaves
like burnt wood. It discolors and doesn’t polish well.)

Depending on the way the coral grew, you can have different
densities, knotholes, gaps between the growth rings, imbedded shells,
etc. Sometimes, you can not achieve a fine polish because the coral
"orange peels" or has a coarse grain. Also, the outer “skin” is rough
to the touch like sharkskin so you would want to remove the outer skin
before doing any bending and forming of branches into bracelets.

The coral is absorbent so you don’t want to soak it or expose it to
chemicals and perfumes. Like polished wood, it scuffs and scratches.
It can shrink even after prolonged drying/curing if exposed to hot

In Hawaii, the harvesting is regulated. Stumps have to be a certain
diameter and you can’t dredge for coral. You have to dive and
selectively harvest. The same can’t be said for other parts of the

Donna Shimazu

Hi Don, Many many thanks for your extremely helpful and informative
response to my “black coral” query.

And yes, I would be grateful if you’d mail me the six pages that
duidn’t make it to publication.

One more question, can you suggest what would be an approximate
ballpark money value for a stick of each type (antipatharian and
octocoral) let’s say the diameter and length of a new pencil?

Cheers & thanks
Hans Durstling
Moncton, Canada

Is there a white version of this coral? I ask because I was once at
the booth of a jeweler who had a few pieces using a material that
looked for all the world like twigs–growth rings, typical branch
structure you would get on a woody plant–but was the most beautiful
creamy-white, so shiny it looked like enamel over silver or gold.
Gorgeous! The jeweler said she had been sold it cheaply by a guy from
Alaska who said it was white coral he found on the beach. I couldn’t
help but wonder whether it was some kind of petrified wood. I don’t
have access to any–too bad!–I’ve just wondered about it ever
since. --Noel

Darcy, Far be it from me to argue with anything you say. But I would
very much like to point out a few things. People around the world
have been making jewelry, trinkets and carvings with black coral for
centuries. It has, by and large, been a cottage industry and was used
by natives or art craftmen at level that its existance went largely

The placement of Black Coral on the endangered species list was the
result of long research on the world reefs and was part of a much
larger enactment that covered many kinds of coral and reef animals. In
fact, read the portion of the Engandered Species List that includes
Black Coral, to find that it only mentions the Antipatharian Black
Coral (deep water variety). The soft shallow water variety is not
even called Black Coral but is buried in the sections concerning
Octocorals (aka Gorgonian). The destruction of reefs that caused Black
Coral to be put on the list had nothing to do with harvesting for
jewelry or craft purposes. But resulted from pollution, fishing,
diving, ship groundings, natural disease, etc. Only since the 1950’s
when deep water coral was discovered around HI, was there any
proliferation in its harvest for jewelry. Shortly thereafter, it was
put on the endangered list and live harvest was, and still is, tightly
regulated. Furthermore, at 200’ or more, there are very few people
capable or willing to risk their lives collecting it live.

I would never venture to say that some unscrupulous people don’t
flout the law and go around the regulations. But they would do that
just to obtain the coral for use in fish tanks much less for jewelry
etc. But the deep water BC is very expensive and so the market is
contained. The soft BC is so readily available from beaches that
there is no need to harvest it live. After storms, it often piles up
on SOFL beaches and beach cleaners rake it up and dump it into the
landfill by the ton! Knowing that, could one say, “leave it for the
beach cleaners… or let it rot, the crafts/jewelry market might
encourage harvesting of the live coral”! I would like to make a bet.
I bet there aren’t more than a few dozen people in the US who produce
more than a few dozen pieces of BC jewelry in a year. Even the
Caribbean tourist trade in BC would not begin to use what Mother
Nature harvests natrually and deposits on the beaches.

One more thing. Unless collectors are terribly careless and throw
their picnic remains around the beach, there is no pollution caused by
walking along the beach on a fine summer day collecting dark brown
’sticks’ that have washed up. All thats left are foot prints and they
will disappear at high tide.

I say its would be a huge waste not to use what has been provided.
Gulp! My soap box broke down, sorry.

Cheers from Don at The Charles Belle Studio in SOFL where simple
elegance IS fine jewelry.

Noel, Some time ago, a friend traded some ‘Alaska coral’ for some
Florida black coral. It is exactly as you describe it though the
pieces are very small. I have to admit I know little or nothing about
it as yet. You are right though, it is pretty stuff.

Cheers from Don at The Charles Belle Studio in SOFL.

    Is there a white version of this coral? 

Noel, There is Alaskan coral. It can be off-white, greyish, tan, to
brown. It looks quite woodlike with grain lines. Then there is gold
coral in Hawaiian waters which is quite rare and comes from VERY DEEP
waters. You need a mini-sub to harvest it and it is protected though
recently, a small harvest was permitted. This coral can be metalic
gold to deep metalic brown with lots of different caramel and glittery
browns in between. It’s pretty stuff but it’s more difficult to work
with because the growth rings often come apart when pieces are sliced.
Also, when cabbing the material, sections can shear off. Sometimes,
it is necessary to impregnate the material with some kind of resin
under vacuum in order to work with it.

In the early days, people used to fill the gaps between the growth
rings of black coral with white epoxy fillers. This would create a
contrast pattern in the slices.

Donna Shimazu