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Africa Blue


#1

OK, all you gemologists. I’ve got another mystery stone. It was sold
to me as “Africa Blue.” I first guessed it to be a jasper, but have
come to the conclusion that it’s probably something else, such as a
sodalite blend. It’s harder than serpentine, but not as hard as
jasper, but close. The striations are more like they were blended as
a liquid than layered, such as one sees in jasper. There’s a picture
on my web site in the “jasper > gray jasper” section. It’s different
than sodalite in that it has some gray and brown. The blue is
extremely deep navy, like very dark lapis lazuli. It has a little
white, but it doesn’t seem to be blended in the same pattern as
sodalite. Any idea what it might be?

Susan
Sun Country Gems
www.suncountrygems.com


#2

Continue from:
https://orchid.ganoksin.com/t/africa-blue

Any idea what it might be?

Sorry Susan. As usual, it’s impossible to positive ID from a photo.
Especially from one and two halves of beads. The only way to be sure
is by regular testing.

James in SoFl


#3

I bought some years past and it turned out to be Dumorterite.

Judy Shaw


#4

I’ve seen sodalite that looks like that. Is is at all fluorescent
with SW or LW UV? Sodalite can occur in greys, brown and white as
well as dark blue. One of my favorite varieties of sodalite is
hackmanite…and it’s not blue at all!

Check it out:
http://luminousminerals.com/greenland/tenebrescence.shtml


#5

A stone that looks like sodalite yet different is BLUE QUARTZ.

I have some from a local collection site and it looks VERY similar
to this…(we are in southeastern pennsylvania)

just a guess!
-julia potts
julia potts studios


#6
I bought some years past and it turned out to be Dumorterite. 

Judy,

Good call, my wife and I came to the same conclusion based on our
past experience.

Richard Hart


#7

Judy,

You are quite right…Mozambique has large deposits of
dumortiorite and I suspect that Africa blue is that.

Ron Mills, Mills gem Co. Los Osos, Ca.


#8

I purchased some rough very like this on EBay as “swirlstone”. It’s
cutting and polishing characteristics are quartzlike so I would have
to agree that it is likely blue quartz. Thanks for answering my
question before I am faced with selling cabs from it.

Cathy Rokaw


#9

Judy,

I’m going with your ID. My visual says that many of the beads have
the look of dumortierite. In fact, that was my first guess, but went
with jasper because it covers so many colors.

The color pattern is consistent with dumortierite or sodalite. The
hardness says to me that it’s dumortierite.

Thanks!
Susan
Sun Country Gems
www.suncountrygems.com


#10

My personal take on the photographs is that both the answers given
so far are correct! How? Perhaps this material is dumortierite in
quartz :wink: This would explain the apparent viening running through
the material and the dumortierite appearance of the blue colouration.
HOWEVER, this is just guessing and James of SOF is quite right that
you really need to get a piece or two verified to be sure. Especially
if you are going to say “this IS …”. If you stick to “this
is possibly …”, then you may be covering yourself?

Just my thoughts/suggestions.

Nick


#11

I am really disturbed about the misrepresentation of the names of
stones! Lately, all sorts of misleading names have been showing up.
At the recent show in Tucson I got some stones that the dealer
assured me were “mustard jade” from a new mine. I got a few, and
when I returned home showed them to a very knowledgeable friend who
assured me that they were not jade, but were probably dyed quartz.

Whatever happened to truth in advertising??? Does anyone monitor the
dealers in Tucson to assure that what they are selling is what they
are represented to be, or is it caveat emptor???

Hate this misrepresentation of things. Gives us all a bad name if we
inadvertently sell something that is not what we thought it was.
Sorry. Just had to let off a bit of my frustration.

Alma.


#12

Hi Cathy,

Sorry…can’t buy in to “blue quartz” Quartz is never blue unless it
has some other mineral mixed in with it. I guess maybe we have a
semantic issue here;quartzite can sometimes be blue, but only if it
has some mineral that is mixed with it. Chalcedony can be blue, but
it is not a common color. (Blue chalcedony is very pricey stuff ! )
Blue chalcedony has a widespread occurrence in Southern Africa, but
most of it is banded material that is too pastel to be classified as
being essentially blue) Unfortunately, chalcedony is very receptive
to dyeing therefore it can be had in just about any color)

Ron Mills, Mills Gem Company, Los Osos, Ca.


#13
    Sorry...can't buy in to "blue quartz" Quartz is never blue
unless it has some other mineral mixed in with it. 

My understanding is that silicated chrysocolla is blue quartz. Rose
quartz, amethyst quartz, adventurine quartz.

It is similar to three glasses of water, one with pink, one with
purple, one with green food coloring…all are H2O, the food coloring
does not change that each is H2O.

Lapis is composed of minerals where the blue is part of what makes
lapis what it is.

Beryl can be green; emerald, blue; aquamarine, or yellow; heliodor.
What makes it the color it is not part of what makes it chemically
beryl.

Richard Hart


#14
    I am really disturbed about the misrepresentation of the names
of stones! Lately, all sorts of misleading names have  been showing
up. At the recent show in Tucson I got  some stones that the dealer
assured me were "mustard jade" from a new mine. I got a few, and
when I returned home showed them to a very knowledgeable friend
who assured me  that they were not jade, but were probably dyed
quartz. 

Unfortunately, jade may be the most widely used misnomer for many
gem materials. It’s all over eBay, rock & gem shows and even jewelry
stores whose owners simply don’t have the knowledge or ability to
identify those materials with regular gemological testing. Even
worse, the number of people who have been selling gems and jewelry
are buying into green “amethyst,” something that is gemologically
impossible is staggering. Referring to this pale, uninteresting
green quartz green “amethyst” is like calling citrine “yellow
’amethyst.’” Selling this irradiated green quartz as amethyst is
wrong, but two members of my local rock and gem club bought some and
are still referring to it as green “amethyst.”

    Whatever happened to truth in advertising??? Does anyone
monitor the dealers in Tucson to assure that what they are selling
is what they are represented to be, or is it caveat emptor??? 

No, nobody monitors gem dealers anywhere, much less Tucson. At
least, not actively. It takes legal action to rectify a problem if
the dealer who ripped you off won’t give a refund. The gem and
jewelry business is like any other: know what you are buying through
education. Arm yourself with knowledge, and you won’t lose $6k on
that blue dial, two-toned Rolex Submariner copy (they’re quite
convincing unless you know what to look for). Put down your
Presidium Duo-tester and learn how to use a refractometer,
polariscope, SG liquids and loupe, and you will never have to caveat
your gluteus maximus again.

At least in the case of this Africa Blue, there isn’t a serious
misnomer occurring. The owner could as easily call it Asian Azure
and not step on any gemological toes, but it doesn’t represent what
the material actually is, any more than Africa Blue does. It may
well be dumortierite, but even having verified similar materials in
the past as being that mineral, claiming that another mineral is
also dumortierite on the strength of one photo of a bead and two
bead halves on a web page is not a valid method of gem
identification. I’m not suggesting that everyone enroll in several
thousand dollars worth of GIA education. There are many books on the
subject, as well as on-line info.

Like practically all fellow lapidaries I’ve met, my fellow
gemologists are more than willing to help others learn to use
gemological equipment and separate gem materials. They probably
won’t loan theirs out, but will show you how to use yours. And yes,
a good quality refractometer costs upwards of $500 - 600, but a lot
of people will lose more than that the first time they buy
misrepresented goods. I can only imagine how much has been lost on
type C jadeite bangles that break in half the first time they were
worn. Don’t be afraid to ask a local gemologist for help. That is,
help in learning how to use your equipment. Don’t expect them to use
their hard-earned knowledge to ID for you. After all, that
hard-earned knowledge is how we make a living.

And that’s the key phrase - hard-earned knowledge. Don’t expect some
non-existent authority to police the gem world for you. If you’re
not willing to earn the knowledge, don’t be surprised when your
"Transvaal “jade” turns out to be hydrogrossular Garnet.

James in SoFl


#15

Dear Alma,

If you are going to dive into the gemstone pool you had better learn
to swim !

The name of the game is knowledge. Deception is deeply imbued in
human nature. Modern merchandising and politics are deception games.
Hucksters and politicians are Machiavellian manipulators who will
dupe you at every chance.Unfortunately, many gemstone purveyors are
not far behind. Romancing the stone gets out of hand at every
opportunity. You do have legal recourse if the cost of litigation is
not too daunting. Fraud is definitely a crime. Meanwhile…your
best defense is knowledge. You can’t be an intelligent buyer of gems
with knowing a generous dollop of mineralogy and gemology. I hate to
be too specific, but I suggest that you be especially wary of hoaky
names that come with some oriental orders. Ask questions. Very often
these people don’t even know that they are walking on thin ice.

Ron Mills, Mills Gem Co. Los Osos, Ca.


#16

Believe me, I’m am as frustrated by the inconsistent and incorrect
naming of gemstones as everyone on this list. In fact, maybe more
so, because I am the “responsible” party who is trying to sell the
stuff. I really try to be accurate, but when the source (even the
factory that cuts the stuff) is unclear, then what’s a retailer to
do?

I want to thank everyone on this list who has helped me ID many of
the beads that I sell. Even though it has totally confused my
customers to find “yellow jade” and “new jade” in the serpentine
category, I think it helps to be as honest as possible in the
reputation arena.

If I had lots of time on my hands, I’d pursue the gemologist
credential, but I don’t, so I can’t. That’s going to remain a hobby
and research area.

However, I do have good news - if you’re ever in Albuquerque, I’m
opening a shop in Old Town next month. This has been about 5 years
in the making, and it’s finally going to happen. I signed the lease a
couple days ago. So it’s really going to happen. I’ll be in the Don
Luis Plaza (right next to the old church in the 2-story pink mall
with the plaza that has a fountain in the middle.) Anyway, I think
it’s going to be a great location and hope if you can stop by that
you’ll ID yourself as an Orchid member. You’ll get extra credit in
the customer service arena:)

Susan
Sun Country Gems
www.suncountrygems.com


#17

ron,

turns out dumortierite or dumortierite quartz is also known as BLUE
QUARTZ. i found this info on the internet on a mineral collecting
site…thought it might help clear this up. so sorry, it seems “blue
quartz” to be a legit term in mineralogical circles. Is it possible
that different terms are used or acceptable in mineralogical/lapidary
or gemological circles???

  Dumortierite is a boro-silicate mineral that is used as a
  popular ornamental stone. It has a deep violet to blue color
  that is very attractive and unusual. Although it is not used as
  a gemstone due to a lack of clarity, it does have good hardness
  and a bright color. 

  Massive dumortierite can be carved into cabochons, beads,
  sculptures, eggs and spheres. A variety of quartz called
  dumortierite quartz is massive quartz colored blue by included
  crystals of dumortierite. Dumortierite can be misidentified as
  other ornamental stones such as sodalite, lazurite and
  lazulite. Blue sodalite has more white portions and is much
  lighter in density. Lazurite and lazulite are not fibrous. In
  China, some dumortierite has been used as an imitation lapis
  lazuli in carvings. 

  Dumortierite is related to several other nesosilicate
  boro-silicates such as grandidierite, harkerite, holtite,
  kornerupine, magnesiodumortierite, prismatine and werdingite.
  Dumortierite is far more common than all of these. In fact, it
  is the most common boro-silicate with the exception of the more
  common members of the Tourmaline Group. 

  Dumortierite is commonly found in aluminum rich metamorphic
  rocks in contact metamorphic regions and in some pegmatites. It
  can alter to the mineral pyrophyllite. Dumortierite is named
  for the French paleontologist, Eugene Dumortier.

julia potts
julia potts studios


#18

Richard,

I certainly appreciate your game of logic…much of what you say
is very plausible, but does not fall within the confines of
mineralogical discipline. 'Silicated chrysocolla" is somewhat of an
oxymoron inasmuch as chrysocolla is simply a copper
silicate…not blue quartz. Silicon is a component of many
minerals, but just because it is does not mean that all minerals
containing silicon are varieties of quartz. Lapis lazuli is
certainly colored by a single mineral, but it is not a mineral…it
is a rock comprised of many minerals. Actually, calling citrine
yellow amethyst is a lot closer to the truth than most people
realize inasmuch as most citrine is heat treated amethyst. In
reality, quartz, in it’s crystalline form, is rarely colored except
for amethyst and citrine. Rose quartz can also be crystallized, but
is extremely rare. Citrine from the deposits at the Ametrine mine in
Bolivia can be heat treated to revert to amethyst, but amethyst from
other mines will lose it’s color when heated… The subject of color
in minerals is complex and elusive…whereas the chemical
constituency of minerals is quantifiable and fairly constant.

Ron Mills, Mills Gem Co. Los Osos, Ca.


#19

SoFo,

 And yes, a good quality refractometer costs upwards of $500 - 600,
but a lot of people will lose more than that the first time they
buy misrepresented goods.

Most of my goods cost under $50.00, so a refractometer is not within
the confines of either myself or my customers. However, you need to
understand that I certainly don’t undervalue the education or work
entailed in becoming a gemologist. I highly respect their work and
knowledge that results, not to mention the cost of equipment.
Hence, my questions to the group. I’m at a low budget level right
now.

I’m not a gemologist, nor do I plan to become one. I’ve spent 20+
years learning the computer trade. My new venture is selling beads.
No, I’m not an expert. However, I do seek knowledge that I don’t
have. I am up there in years, so I don’t have a lifetime to devote to
a new career. However, I am willing to take the time to find the
that will help me be truthful in advertising. That’s
not a small task, but certainly far less than the work of becoming a
gemologist. Kudos to all who have attained that high standing. I
only wish I could afford one on my staff. However, I have a staff of
zero right now, so you’re going to have to wait a while for a
position with my company.

If I was independently wealthy, then I would hire a gemologist. But
I’m not, so I do the best I can. I hope everyone on this list
understands that I’m simply trying to be an honest vendor, not a
perpetrator of misrepresentation.

I haven’t said anything previously about this, but here goes, . . .
I’m opening a shop in Old Town Albuquerque later this month. It’s
big step, 4+ years in the making. If you’re in Albuquerque from
August '05 on, please stop by the Plaza Don Luis (right next to the
plaza) and pay me a visit. I’d love it if you’d ID yourself as an
orchid member. You’ll at least get a big smile.

Susan
Sun Country Gems
www.suncountrygems.com


#20
    turns out dumortierite or dumortierite quartz is also known as
BLUE QUARTZ. i found this info on the internet on a mineral
collecting site.....thought it might help clear this up. so sorry,
it seems "blue quartz" to be a legit term in mineralogical circles.
Is it possible that different terms are used or acceptable in
mineralogical/lapidary or gemological circles??? 

Not really - dumortierite is still dumortierite, even when found as
an inclusion in quartz. That does not make dumortierite-included
quartz “blue quartz” any more than a heavily garnet-included diamond
would be a “red diamond”

   Dumortierite is a boro-silicate mineral that is used as a
popular ornamental stone. 

Accurately, dumortierite is an ALUMINUM borosilicate mineral, which
fact should make it obvious that is simply isn’t quartz at all. But
for those who still doubt, here is more evidence:

Quartz forms in the hexagonal crystal system, dumortierite is
orthorhombic. Dumortierite’s optic figure is biaxial negative, while
quartz is uniaxial positive. Dumortierite’s chemical composition is
(Al,Fe)7BO3(SiO4)3O3, and quartz’ composition is simply SiO2. These
three fundamental differences should be enough to prove to any
lapidary, mineralogist, gemologist or jewelry store owner that
dumortierite is not blue quartz, nor is it quartz in any form.

     Massive dumortierite can be carved into cabochons, beads,
sculptures, eggs and spheres. A variety of quartz called
dumortierite quartz is massive quartz colored blue by included
crystals of dumortierite. 

And here you prove the point, yourself. This quote doesn’t call it
blue “quartz” rather, dumortierite quartz. That is acceptable. It is
also acceptable to say that the quartz is colored blue by
dumortierite inclusions, but it is incorrect and misleading to say
that it is blue “quartz.” There may be, as you said, a mineral
collecting site that uses the misnomer blue “quartz” for
dumortierite quartz, but anyone can author a web page and say
whatever they wish. You’re better off looking at the chemical
composition and optical qualities of the material to determine
precisely what a mineral is rather than relying on somebody’s web
page or blog. You don’t need gemological credentials to do it,
either.

James in SoFl who would rather be gemologically accurate than
mineralogically vague. It cuts down on the refunds.