Rainbow Calsilica - natural or manmade?

Jewelry Discussion
11 
Folks, this stuff is automotive paint, plain and simple. It came
from Detroit in years past when it was jokingly called
"detroitite," and now it comes from Mexico where auto manufacture
is cheaper, and called "rainbow calsilica." It'll probably come
from India next. Wonder what they'll call it then?

The difference, I think, between Detroitite and “Rainbow Calsilica”
IMO is that the latter has ground-up minerals intentionally added to
throw gemologists off the track. Detroitite, aka Fordite, was
comparable to Zincite (the Polish stuff) in that it was an
unintentional man-made stone, the chippings from the walls of auto
manufacturers’ paint booths. “Rainbow Calsilica” OTOH, is an
elaborate and deliberate fraud. I first saw the stuff in Quartzsite,
and got a whole sales pitch from the dealer complete with photos of
the supposed “vein” in the mine it was allegedly obtained from. It
didn’t look natural; it ISN’T natural. Many lapidaries were skeptical
about this material from the start, but at this point, with all of
the info available, I am inclined to say anyone still peddling it as
natural is either a buffoon or a scoundrel.

Lee

12

Doctor,

Thank you for the explanation. I think this batch of “rainbow
calsilica” is both batches we buy - first and last! Because I want to
be upfront with my customers about what we sell, I can hear the
conversation with a customer:

Customer: “Gee, those are very pretty beads, but they are so
expensive, what kind of stone is that?”

Me: “Well, it’s very unique. It comes from Mexico and believe it or
not, it’s just layers of auto paint.”

Customer: “And you’re asking $40/strand for AUTO PAINT?? That’s a
ripoff !!”

and the last we see is the customer walking off because he feels
insulted that we would try to sell clumps of auto paint as a stone at
premium prices. I have GORGEOUS hand carved malachite for a lower
price that is going begging. I can’t see “morphed paint chunks” (by
whatever name they are called this week) selling better than the REAL
stuff.

This conversation has led me on a search through “detroitite”,
“fordite”, “motownite” and “Detroit Agate” - an interesting journey.
Whatever it’s called, it is a pretty item.

I never did get a response from the e-Bay seller who claimed to have
an analysis from a “Geologist/Chemist” from some big “University Back
East” proving it’s a natural stone. I mentioned to the seller that I
have several contacts at “Universities Back East” - generally in the
geology departments, as luck would have it. And my hubby has a degree
in chemistry, so he would be able to translate such an analysis IF it
exists. Maybe I should quit holding my breath waiting for a reply?

All I can say for sure is - apparently in the beading world, this
stuff, no matter what it’s called, is selling like wildfire! So -
maybe it’s questionable heritage isn’t held against it, after all.

Deb
AZ Bead Depot
Apache Junction, AZ
www.azbeaddepot.com

13

If this is automotive paint (and I don’t doubt this for a minute),
then one wonders about the potential for toxicity when the "stones"
are worn against the skin. There may be cadmium pigments and other
nasties involved.

Brian Corll
Vassar Gems

14

As a test, I contacted six sellers of “rainbow calsilica” on eBay
and informed them of the probable identification of the calsilica as
automotive paint (hey - let’s call it “Duronite” !) or some other
pigmented material. Only one showed any real interest in finding out
what the stuff is. One said he didn’t care - as long as the idiot
public buys it, he’ll sell it to the idiot public. Four out of five
said: “Thanks for writing”. You know what that means. :wink:

Brian Corll
Vassar Gems

15

Assuming for a moment this stuff is automotive paint and sounds and
looks like it is (I worked as an auto painter years ago and seen this
layer effect), the potential for toxicity when the “stones” are worn
against the skin is a “maybe” in my opinion. As the paints don’t
leach with skin contact that I know of.

BUT, grinding, filing, sanding, burning… then things will get
nasty. If the paints are in fact from the 60’s and earlier (as I’ve
read) there can be any number of heavy metals, lead, cadmium and
dozens of other nastys (these are petroleum based paints remember)
that you really don’t want to breath or ingest inadvertently.

While it won’t likely kill you in a instant (well burning maybe it
could), long term exposure IS really bad.

16

I’ll add my 2 cents to the confusion. Recently I was speaking with
Archie of Archie’s Rock Shop in Mason, MI, USA and he indicated that
there had been a pottery factory in the area where the rainbow
calsilica is mined. It is his opinion that the factory workers simply
dumped the excess glazes out the door at the end of the day and that
the glazes percolated into the rock creating the layered effect.

“Fordite” is automobile paint that was dumped on the factory floor.
I’m no expert, but the layers in most “Fordite” cabs I’ve seen are
very opaque while the rainbow calsilica has a translucency that seems
different to me. So, I thought Archie’s explanation (pottery glazes)
seemed reasonable.

Debby Hoffmaster

17

If this is automotive paint (gee we live in a weird world.), then we
should start seeing some of the more recent madly popular metallic
copper colours soon, don’t you think?

Will be watching for it myself.

stephanie

18

Toxicity of Rainbow Calsilica

I have the same question about “rainbow calsilica” or “Duronite” as
I think we should call it. I wonder about the presence of pigments
such as the cadmiums which can be troublesome.

I just found a site on the web which references the composition of
topcoat automotive paints. Among the pigments used are the lead
chromates (yellow, oranges, etc.) and iron oxides. If you’re
cutting/cabbing any of the "newly found like Detroitite,
calsilica, or whatever, watch out for the inhalation of these
pigments, or transfer through the skin.

Brian Corll
Brian Corll, Inc. (BCI)
1002 East Simpson Street
Mechanicsburg, PA 17055

19 
All I can say for sure is - apparently in the beading world, this
stuff, no matter what it's called, is selling like wildfire! So -
maybe it's questionable heritage isn't held against it, after all.

First, Deb, you thanked me for my explanation and, you’re very
welcome. I would like to address the above, too.

The reason for that is because its questionable heritage is mostly
unknown. People everywhere are buying it under the assumption that
it is a natural stone because the people selling it are claiming just
that. It is a shame, because it really is pretty material that would
do well on its own, given the right marketing angle. But hanging a
name like rainbow calsilica on it and selling it as natural is just
criminal. The sad part is that if enough customers get angry about
being ripped off by this scam, our entire industry will suffer from
lack of consumer confidence.

Seriously, people pay lots of money for jewelry made with found
objects, beach glass and various “folk art” pieces. They’ll pay just
as much for paint beads, too. Remember pet rocks? There’s absolutely
no reason for anyone to intentionally mislead the public about gem
materials. It’s bad enough that some companies romanticize crappy
stones with weird misnomers, but “natural” rainbow “calsilica”
(“mined” in Mexico, no less), is going too far. Especially when they
know how many hobbyists there are on eBay and at the gem and jewelry
shows. Selling this stuff to them is like shooting fish in a barrel,
and it stinks on ice.

Please pardon my rant, I’m just an old hippie who still wants to buy
the world a Coke.

James S. Duncan, G.G.
James in SoFL

20 
I thought Archie's explanation (pottery glazes) seemed reasonable.

Sorry, but as someone who knows about pottery glazes, it is not
plausible. The glazes would have to be fired to have any color or
translucence, and fired glazes would be on pots, and would not be in
a form that could be dumped or seep into the ground… and on top of
that they don’t “spoil” so there would be no reason to dump them on
the ground.

Noel

21 
If this is automotive paint (gee we live in a weird world.), then
we should start seeing some of the more recent madly popular
metallic copper colours soon, don't you think?

No, evidently not. I have read that paint is now applied
elecrostaticly so that it all ends up on the car-- no more spray
booths, no more layers of paint on walls, no more fordite. Of
course, if this stuff sells well, someone will start making it
directly, but you know, then the quality goes out the window ;>)

Noel

22

Based on all of the anecdotal evidence I’ve been able to gather
along with some scientific investigation, I would say that what the
Mexicans are doing is taking cans of automotive paint, mixing it with
calcium and silicates (makes the stuff seem like something from the
ground) and paraffin to add translucency, and laying it down either
in distinct layers or swirled via the Jackson Pollock technique. Then
they wait for the stuff to harden thoroughly (baking will certainly
help) and then “mine” it and sell it off to cutters. Sound like a
reasonable analysis?

Brian Corll
Brian Corll, Inc. (BCI)

23 
No, evidently not. I have read that paint is now applied
elecrostaticly so that it all ends up on the car-- no more spray
booths, no more layers of paint on walls, no more fordite.

I know that powder coat paint is done this way, but I’m not sure how
many auto manufacturers are using it, as it is still quite
expensive. The powder is charged negative or positive (opposite of
the metal upon which it is deposited), then baked at temperature and
time until it flows to a smooth finish. Painters on TV shows like
American Chopper and American Hot Rod describe it as a very hard
finish that is more like chrome than paint. They do spray it in
booths, but those booths also have enormous exhaust fans to filter
out overspray.

One thing for sure, any overspray left in the booth would be useless
as “fordite” as the entire booth would have to be baked in order to
get the paint to flow out of powder form. But I’m still not sure how
many are using this type of paint, and I don’t think it works with
other types of paint.

James S. Duncan, G.G.
James in SoFL

24 
No, evidently not. I have read that paint is now applied
elecrostaticly so that it all ends up on the car-- no more spray
booths, no more layers of paint on walls, no more fordite.

I know that powder coat paint is done this way, but I’m not sure how
many auto manufacturers are using it, as it is still quite expensive.
The powder is charged negative or positive (opposite of the metal
upon which it is deposited), then baked at temperature and time until
it flows to a smooth finish. Painters on TV shows like American
Chopper and American Hot Rod describe it as a very hard finish that
is more like chrome than paint. They do spray it in booths, but those
booths also have enormous exhaust fans to filter out overspray.

Autos are painted by mostly robots these days using pretty much
standard auto paints (acrylic lacquers and other high tech two part
paints), but the body IS charged elecrostaticly to attract more paint
particles to the body and reduce overspray. It is then “baked” with
lamps mainly to speed dry time and to harden the finish.

Powder Coat isn’t really “paint”. Powder Coat is a dry powder ( a
type of plastic) that is sprayed (dusted) and elecrostaticly clings
to a item. It is then baked in a oven of sorts (much hotter than a
auto paint drying booth) into a smooth hard finish. And while it’s
tough, it’s not near as tough as chrome as chrome is metal finish.

Thank You
from
gWebber - Feverdreams.com

25

I could swear that I saw something on TV recently (well, the last
time I actually watched TV, which has been about a year) that showed
an auto manufacturer dipping auto bodies in huge vats of paint. I
don’t know which maker this was or how many makers do it, but it
completely did away with the need for human involvement (other than
to run the machine, sort of like running an overhead crane in a steel
mill) and obviating the hazards of auto paint. If anybody else knows
what I’m talking about, let me know.

Brian Corll
Vassar Gems

26 
I could swear that I saw something on TV recently (well, the last
time I actually watched TV, which has been about a year) that
showed an auto manufacturer dipping auto bodies in huge vats of
paint.

Auto bodies are dipped for a number of reasons.

On new cars, they can be dipped to clean the metal prior to paint or
to zinc coat the metal and maybe other things. But dipping for paint?,
while I don’t doubt it may have been done some where at some time, it
would however make for a lot of problems, runs, drips, uneven paint
thickness and wasted paint. So I would think the process was short
lived.

Acid dipping can be used to remove paint, rust and body filler.

Thank You
from
gWebber - Feverdreams.com

27

Here’s what I know, for what it’s worth. Rainbow Calsilica is
definitely stone. Some lapidaries have told me it occurs naturally
near some turquoise mines; some say it’s a man-made conglomerate. I
actually own a chunk of “rough” and it’s interesting material - very
soft. If it’s cut well, you can get some neat-looking cabs, if
that’s what you like (I do).

“Fordite” is a different beast. A few years ago I bought some from a
nice woman at a local rock and gem show. She told me her late father
had worked in a Ford factory (hence the name, I guess) in the 1930s.
Periodically, they would scrape the layers of different colored
sprayed paints off the floor of the assembly line, and some clever
dude found that he could work it into cabs using modified lapidary
techniques. She was selling the last of the finished jewelry her dad
had made with it, and some remaining scraps of the “raw” material. I
bought some,just as a curiousity; still don’t know what I’ll do with
it, but it’s kinda cool! I doubt much of it can be found anymore,
but I’d love to have more.

Rhona

28

Hi, Rhona-

Rainbow Calsilica is definitely stone. Some lapidaries have told me
it occurs naturally near some turquoise mines; some say it's a
man-made conglomerate. I actually own a chunk of "rough" and it's
interesting material - very soft.

This begs the question; what leads you to believe that Rainbow
Calsilica is a stone? How are you defining “stone?” It is reported to
have some ground up calcite and silica in it, so I could go along
with it containing stone, but as for its being a stone, it is hard
for me to get there.

The presence of ground-up silica and calcite do differentiate it
from Fordite, but other than that, and the fact that one man-made
substance is accidental while the other is made intentionally, they
are quite similar, I think.

Lee

29

Rhona,

Please.

Calsilica is a man-made product, pure and simple. So, what you
"know" is wrong. Sorry to be so blunt, but this is not a matter of
opinion. Lapidary Journal published their findings on it some time
back. I’ts man-made, and a ruse. GIA did the same thing. It’s
man-made. There is an absolutely amazing amount of poor information
or opinion passed off as fact on this list.

Since everyone posting here has a computer, why is it so difficult
for some folks to not use Google or another search engine to do some
mildly exhaustive research for themselves rather than ask someone
else to do their research? Is it laziness, or what? It seems that
when erudite and experienced answers are given by those who have
been personally and financial successful in our trade, those remarks
are ignored and ignorance is passed on. What am I missing here?
Folks, Calsilica is a man-made product, let’s put it to rest.

Wayne Emery

30

I agree that we need to put this thread to rest. Rainbow calsilica
is a fake. Period.