Rodanite

I have friends in N. CA who wrote the following: “We have discovered
and identified a rock called “rodanite” on our property. I was told
they make jewelry from this stone. Do you know anything about it?”

I checked the archives and came up with nothing, so wondered if
anyone on Orchid has any info about this rock.
Louise Gillingham, San Diego @lgillin1

Louise,

I believe that the correct spelling is rhodonite. If you do a search
using this spelling you might be more successful.

Joel
@Joel_Schwalb
www.schwalbstudio.com

What they probably mean is rhodonite. It is a pinkish rock and is
used for jewelry. Some have black streaks in the pink. An easy stone
to slab and cab. Steve Ramsdell

Rhodonite maybe? Rhodonite ranges in color from pink to red, usually
with black veining due to the presence of manganese. The name comes
from Greek “rhodon” meaning rose.

Hi Louise, I think this might be spelled rhodonite. Rhodonite is a
rose-pink rock with grey and black veining used in making cabochons.
Some is found in British Columbia. Karen

Probably rhodonite you are looking for Louise. I believe you can
find it in CA but I think Ron at Mills Gems should be able to answer
that for sure.

Daniel R. Spirer, GG
Spirer Somes Jewelers
1794 Massachusetts Ave.
Cambridge, MA 02140
@spirersomes
http://www.spirersomes.com

Check “rhodonite”. Pink to pink and white, opaque to transluscent.
Very pretty. May also have some black inclusions.

Dave

Dave Sebaste
Sebaste Studio and
Carolina Artisans’ Gallery
Charlotte, NC (USA)
dave@sebaste.com mailto:dave@sebaste.com
http://www.CarolinaArtisans.com http://www.CarolinaArtisans.com

Dear Louise,

Your friends’ “rodanite” is really “rhodonite” and it is indeed used
in jewelry (especially for beads) as well as for ornamental carvings.
It’s typically pink (from pinkish grey to hot pink at its best) with
patterns of black matrix. It isn’t particularly valuable but can be
very beautiful.

Beth

louise - that’s probably ‘rhodonite’ - i have some rough pieces from
that area. it can be from a deep dusty pink to a salmon pink -
sometimes it has black veins, sometimes it has black dendritic
’trees’ it. i found a super piece without any black inclusion - it’s
a little more stable, less crystalline than rhodochrosite. takes a
very good shine. ive

Louise, I would think that this is probably Rhodonite, which is
manganese silicate. Pink to flesh-red, usually with some white also in
a sort of marbled effect, and black veining. Hardness 5.5-6, which is
not as hard as quartz, but hard enough to take a good polish. You
might want to check with one of your local rockhounders’ clubs; there
are a number in your area.

Cheers!
Margaret

Dear Louise, I’m not sure if American spelling is different, but we
have a mineral in Australia named rhodonite. It comes in various
shades of pink and red with black patterning. It’s a manganese
silicate and can be a bit splintery but it is a very tough mineral
with a hardness of around 6. There are some beautiful shades of opaque
pink and red to be found. Hope this helps. All the best for the
season. Kind regards Rex from Oz

Try this spelling: rhodonite. If it’s the same thing… it’s pink
mottled with black. It can be found in California, and is used for
jewelry. This site shows specimen pieces and gives mineral background
on it. (Click specimens to see them.)

http://mineral.galleries.com/minerals/silicate/rhodonit/rhodonit.htm

There are rhodonite spheres here:
http://www.spherestoyou.com/Sshoppe/rhodonite.htm

The rhodonite I’ve seen from Northern Cal generally has more black in
it.

HTH, Carol @Carol_J_Bova

Dear Louise, Your friends in Northern California most likely are
referring to Rhodonite, a manganese silicate, pink in color and
mottled with black. There is a deposit near Happy Camp in the Coast
Range and several deposits in Plumas County especially in the area of
Indian Valley ( Taylorsville ) Rhodonite is nearly as tough as Jade
and can be difficult to polish. It has a limited market, but good
material is highly sought after. You might suggest that your friends
contact me as I am particulary found of this material and regularly
process it into designer cabochons. Ron at Mills Gem, Los Osos, CA. (
Tyson Wells Early Show, Space I-30, Quartzsite, Jan 5-14 )

I suspect they mean rhodonite, Louise. When we belonged to the San
Francisco Gem and Mineral Club they had a rhodonite claim up in the
coastal mountains, not quite as far up as Redding. It has a nice
pink color to it there. Other places it has a deep red rose color,
like near Cave Junction, Oregon. At the club mine the manganese
(think that is the right mineral) tends to form little black lines
running through the pink , and so they call it the spider mine.
Outcroppings can be hard to spot until you break a piece open, for it
blackens on the outside. Even pieces that have been in storage for
years can develop a darker film on a cut surface. I haven’t heard of
this being a detriment to using it in jewelry, though. One year a
fellow from Reno was getting quite a bit because his wife wanted him
to tile the bathroom with it. I always wondered how that turned out.
Some of the prettiest stuff is made of puffs of pink crystals in snowy
white quartzite. They called it Appleblossom. Sincerely, Rose Alene
McArthur @O_B_McArthurs

I believe the stone is spelled rhodonite. It is an aggregate, often
pink with black inclusions. Its refractive index is 1.733-1.747 with
a birefringence of 0.010-0.014. Its Mohs hardness is 5 1/2 to 6 1/2.

It’s fairly common and incidently, the first stone I ever set. It’s
in a ring that my daughter wears. I paid $1.00 for the stone, and
it’s ugly, lousy color and cut. Now I have some really pretty
rhodonite stones, but I have to get them set.

Oh well, all the Christmas stuff is done. Now to the eggnog. Happy
holidays to all, see you in Tucson.

What I have been seeing about Rhodonite thus far is only the tip of
the iceberg.

The colors of Rhodonite in its massive form run a large gamut from an
ugly pinkist tan, through beautiful pink to bright red. It may also
be found with violet and purple as well as some swirling yellow, white
and a bit of green now and then. I currently have samples of all of
those colors except for the green though I have seen it. The
crystaline form usually is bright pink to red.

It comes from many places. They mined it on Taiwan for a number of
years during the 70’s, Japan is reported to have some, CA has produced
it on and off for many years (so was not surprised to see someone has
found a new deposit), Franklin, NJ, Sweden, USSR, Australia, also
Massachusetts, Colorado and Rhode Island. There are probably others.

Normally found incident with manganese oxides, sometimes in massive
form, hence the ‘spiderweb’ lines inside. Often it looks just like a
heavy black metalic stone. When a chip is taken off, just below the
surface it will be brignt pink. Hardness 5.5 to 6.0. Easy to slab,
carve or cut. If too thin, it will cleave easily but not particularly
heat sensitive. Takes a great polish on several powders but I prefer
linde on hard leather. If there is any undercutting go directly to
diamond wheels/pads thru 50K.

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

G’day; Rhodonite is a manganese silicate, often containing streaks
and veins of manganese dioxide. It can also contain a complex of
calcium and magnesium. It is usually a pretty pink colour and is
mostly opaque, although it does occur in translucent and even
transparent varieties. Unfortunately it does undergo a leaching of
colour in strong sunlight. It has a Moh’s hardness of 5.5 to 6.5, with
a refractive index of 1.74 and 1.51 according to crystal orientation.
The specific gravity ranges from 3.57 to 3.76. Note that it is quite a
bit harder than rhodochrosite, which however is a more rare mineral.
It is sometimes difficult to shape, having a tendency to crumble in
places. I have polished it with wet-and-dry papers on a hard rubber
backing using water lubricant at first and finishing with 400 grit
dry. The final polish can be brilliant using tin oxide and water
slurry on a leather disc. I am told that it takes a good polish too
with Linde A or chrome oxide. I have never used either. The polished
mineral looks well with silver. We have a small deposit in the South
Island of New Zealand in the Dunedin area on the Otago Peninsular.
Which is where my pieces came from.

I will be sending you, Louise, a picture of one of my small pieces in
a separate mail - when I get my scanner going again. I hope! But
don’t hold your breath! My son is with us for Christmas, and is
updating my computer - partly in bits at present! (The computer, not
Peter.) Cheers, Happy Season,

– John Burgess; @John_Burgess2 of Mapua Nelson NZ where the
weather has been hot and summery - but is turning to high winds and
rain for Christmas! No usual Christmas Day picnic by a bubbling brook
this year!