FMF - Friends of Minerals Forum, discussion and message board

[Conor Quinlan]

....also I believe the overall appearance and 100% complete transformation to cassiterite are fairly consistent with the finds of 1828 from the U.K. but this certainly is not an area I’m highly acquainted with to say for sure.
I plan to ask more than a few other collectors I know during the 2021 Tucson Show, assuming covid-19 has passed. One of the reasons I’m so grateful to be from Tucson!
Can almost always find someone who has the expertise to find out or know for sure where a mineral comes from

[Bob Harman]

Conor, Like it or not, when dealing with truly classic specimens, the original label usually is as important as the specimen. The labels substantiate the provenance of the specimens, making them attractive for acquisition by both hi end dealers and collectors willing to pay substantial premiums for these examples.

Whether mined hundreds of years ago from long extinct classic localities, or formerly in the collections of important people like Philip Rashleigh or Washington Roebling etc, classic mineral specimens are usually not as aesthetically great as those collected more recently. So the label of original provenance is the true value of many of these examples, including even those mineral specimens that are relatively unique from long extinct mining localities.

For me, most important truly "classic" specimens with no original label for provenance = no premium for the "classic" specimen = no consideration for purchase, even from an ethical dealer.
You just can't go around saying "this fabulous specimen was mined 200 years ago, or formerly in the collection of Washington Roebling, but I don't have a label".
My opinion, Bob


As an addendum, this topic of the importance of original labels with truly classic specimens should make for some good discussions on another thread.

[Michael Shaw]

See these topics on original labels.

Preserving old labels

Right labels

Labels and history

Mineral labels as art ;)

Old labels of minerals

Label history

[Conor Quinlan]

Bob, that's certainly disturbing to hear, but I get what your saying & will be making a more serious inquiry rearding the cassiterite's legitimacy today.

This is my 1st "historical" specimen so some of this is pretty new to me. I mean, I knew the piece would be significantly less valuable w/o the label, but didn't imagine it would literally make or break the historical value, I am particularly surprised to hear that a high-end mineral dealer's reputability does little to sway public opinion when it comes to these matters, but I suppose it makes sense.

Thanks for sharing your opinion! If the label is as important as you say then it looks like I may be returning this one :/

[Bob Harman]

Conor,
Several additional points on labels. Did your specimen come with any label or was it totally without a label? In general, labeling all specimens is very important.
It is important to differentiate just any so called "classic" specimen from a truly "historically important classic specimen". The labels are really really important with truly important classic specimens as museums might be interested in these. The label has to be original, as anyone can make a modern label fudging the provenance of the specimen. Specimens from important historic localities or from important collectors collections should always come with the important original labels.

If you are to keep your examples for a number of years, then try to sell any of them with no labels, they would have neither much historic value or, if they weren't particularly aesthetic by modern standards, they might not have much modern collector value.
Proper original (!) labels for specimens of historic value are important. Bob

[Conor Quinlan]

Hello Everyone,

I have many incredible specimens to share this month after expanding my personal collection during this lull.

The following mineral specimens will be posted in random order below over the course of the week. Each post will include (2) specimens with pictures & a short description:

1. Carlsbad-twinned topaz a/f orthoclase
2. Red topaz & hyalite opal
3. Beryl var. aquamarine & tourmaline var. schorl on orthoclase
4. Native copper a/f cuprite with native silver
5. Kunzite covered with bi-colored tourmaline
6. Rhodochrosite a/f bivalve fossil
7. Chunky hexagonal mimetite on matrix
8. Iridescent opal in silica matrix
9. Native crystalline gold

Mineral Posts:

3. High quality aquamarine specimens are a favorite amongst collectors because of their jaw dropping aesthetic nature. The enticing rich blue color in combination with a gorgeous crystalline structure makes this species a must have for any serious collector.
I have wanted a top quality aquamarine ever since I was a kid & this specimen doesn't disappoint with a few unique features!
Features a huge (7.3 cm) long doubly terminated partially clear aquamarine that's uniquely interpenetrated with dark scholar crystal at the center.
Dozens of complex & beautiful scholar crystals cover the specimen as well as several more aquamarine crystals.
Exhibited on a matrix of solid orthoclase which displays an aesthetic pattern of complex twinning & structural modifications.

9. Just acquired a few days ago, normally I'm not as interested in gold specimens, but this native gold exhibits some of the most interesting crystal formations I have ever seen!
Primarily a very rare (1.5 cm) formation made from (6-7) perfectly terminated spinel-law twin crystals!
Several hoppered octahedrons ranging from (1 - 3 mm) in size surround the formation.
Beautiful compact dendritic patterns are exhibited on the opposite side the specimen.
Complete "Floater" crystal with no damage or points of contact!
Exquisite top quality "mirror-brilliant" luster with a buttery yellow golden hue

[Conor Quinlan]

Sorry for the late response, it's been a busy couple weeks.

I agree that labeling is necessary to give a specimen legitimate historical value. I should've introduced the specimen differently; yes, I wish the specimen included a label but the actual mineral itself is more important to my personal collection than the history as I collect feldspar minerals & even without a label it's still a rare ortho pseudo that was most likely sourced from Cornwall between 1828-1860s.
And w/o the label I was able to negotiate a far better deal!

I have read several articles and there seem to be relatively few locations that produce these Carlsbad pseudos, especially more recently (after 1900). I can only find one mine outside the U.K. that produces similar pseudos in Bolivia, but their appearance seems fairly distinct from the Cornwall pieces which have minute tinges of dark red-orange spots. The Cornwall Mine stopped producing these specimens in 1860s. Given this info, I am confident the specimen is from Cornwall, just don't know the exact mining date, but it's most likely before 1860!

[Tobi]

I really like that 11 cm aquamarine specimen from Erongo.
A world-class piece, congratulations!

[Conor Quinlan]

(2 of 4) Update on "Best of the Month mineral specimens":

4. Native Copper a/f Cuprite w/ Native Silver:
I have never been a huge fan of metal based minerals but I was pleasantly surprised by this stunning piece which exhibits copper in a way that was truly aesthetic to me. The sharply defined copper pseudomorph displays intricately defined crystals that maintain a perfect octahedral structure. The bit of native silver that shines though is displayed in the form of a disk along with several other smaller patches of silver which are spread all over the specimen.

7. Chunky Hexagonal Mimetite on Matrix:
Perfect & Beautiful this mimetite specimen shows how stunning the mineral can be when exhibited in the form of larger crystals (up to 1.2 cm). The appearance is somewhat special too with a butterscotch yellow color.

[Tobi]

Superb mimetite crystals!

[Conor Quinlan]

Update (3 of 4) on "Best of Month" mineral specimens for June 2020:

5. Clear Kunzite w/ Bi-Colored Tourmaline:
Being an avid collector of specimens that exhibit multiple minerals I was delighted to discover this fantastic piece. Although the kunzite appears clear a very faint yellow tinge is visible & can be compounded when viewed from the correct angle. The kunzite is also nearly perfect structurally & most importantly adds an aesthetic appeal that's very unique & impossible to achieve with either mineral alone
The contrasting pink & green colors exhibited by the tourmaline are fairly vivid & have a high luster that gleams brightly when lit with lighting. All crystals are gemmy with great clarity & decently low levels of inclusions.

8. Iridescent Precious Opal in Silica Matrix:
Precious opal displays every color of the rainbow with great intensity. Exhibits green, yellow, blue & purple in lower light, then displays orange & red as light intensity increases. Opal completely fills every cavity reaching depths, as well as widths, of up to (2 cm) within & across the matrix. The largest estimated volume of almost solid opal = (2 x 1.5 x 1.5 cm). The inclusion of a silica based matrix made this piece even more appealing as a naturally sourced mineral specimen.

[Conor Quinlan]

Although Silver Amalgams are ultra-rare in nature when they do occur they are generally quite dull in appearance & form in thin sheets.
However, this particular specimen exhibits a far more complex & thick structure, as well as a very unique, highly aesthetic, bronze patina in addition to the silver! More than likely a one-of-a-kind specimen!

(SEM) tested to verify the existence of both Luanheite as well as Eugenite by Prof. N. Rudashevsky (Signed Document w/ Labeled SEM Images).
Also found additional deposits of the following minerals:
Stephanie | Freibergite | Pyragyrite | Polybasite | Acantite | Sphalerite | Arsenopyrite | Limonite | Quartz

[Peter Lemkin]

Wow! Not only rare, but a nice and large specimen. Lucky you.

[James Catmur]

Conor

I am not sure they are 'ultra-rare in nature' as I have a fair number in my collection. They are not common but there are far rarer minerals.

Have a look at this one on the Spanish side

https://www.foro-minerales.com/forum/viewtopic.php?p=151067#151067

James

[Tobi]