FMF - Friends of Minerals Forum, discussion and message board

[Jesse Fisher]

Luis,
Beryl and quartz have very similar RI. Opticon is used on both.

[GneissWare]

Just a few comments...

Opticon is bad as it will yellow with age. Most people are using Epoxy 330 which will not yellow.

As to Europeans not accepting repaired specimens--this means Europeans will not buy Pederneira tourmalines or any other tourmaline for that matter, as very few are intact due to tectonic stresses? This is true of many localities. I suspect that just like here in the USA, buyers want to know if repairs have been made.

An issue that hasn't really been raised is restoration of mineral specimens. As an example, the Alma King, if I remember correctly has a small corner restored on the 15 cm crystal. This was done using tinted epoxy that matches the RI of the rhodochrosite. Is this an acceptable practice? I believe it is as it allows small imperfections to become unobtrusive--but it needs to be clearly labeled. Even the wild groups of Pederneira tourmaline had small portions restored as the crystals chipped upon breaking in the pocket. At the time, the dealer's labels clearly marked repair x 2, restore x 4, etc.

And, as to the comments on antiques...they almost always have some degree of being restored, fixed, refinished, or modified, etc. I worked with a conservator from the Getty Museum, and everything that came in had some work done on it. Its hard to be around for several hundred years without some wear and tear. Heck, I have only been around 50+ years and I am showing wear and tear....I need a repair and restoration ;=))

[Jordi Fabre]

[alfredo]

My first post was mis-read - Please read it again; it does not say the majority of MINERAL specimens have been repaired, only that repairs are increasingly likely the larger the size of specimen one collects.

I'd also disagree with Jordi that repairs are more common in America than Europe; my observations have been the opposite! Perhaps my statistical sample size is not big enough to draw a valid conclusion.

But, as others have pointed out, disclosure is the essential element - then each customer can decide for themselves whether they want it or not.

[Louis Friend]

There are many procedures for the repair, preparation and display of minerals. Many of these techniques require the use of chemicals and chemical procedures that can be a hazard to the collector. The help people require is real and goes way beyond the mere suggestion of use this glue or that glue. What the collector seeks is real guidance and direction, not mere suggestion! And the only way this can be done is by example. I plan to include a section on FMF that details the procedures, chemicals and tools needed to repair a specimen. Like my acrylic stands section it will be highly detailed and will use one of my pieces as the example. However there is a catch! I must first explore the liability issues before posting it, as I will be using chemicals that the average person rarely encounters during the course of their daily activities. Please be patient!

[nurbo]

I guess ultimately its a very personal choice,and a kind of puritanical thing, though its all a question of scale, as soon as you collect a piece and remove it from its natural environment you are manipulating it, I think we all just have our own ideas about how much manipulation is allowed, as we all know when things come out of the ground they are often covered in mud, carbonates, rust or anyone of a number of other things which detract from the beauty of the specimen, do we leave them on there so as not to spoil the natural aesthetic of the piece? Of course not, we dump them in Oxalic or Dithionite or Super Iron out etc etc until we decide the specimen is ready for display. Repairing specimens is, in my opinion, an extension of the prepping process. Though as has already been said disclosure is essential.

[Carles Millan]

[Pierre Joubert]

Buen dia Lluis

Keep on practicing your Afrikaans! I have learned a lot about repairing specimens from this discussions. I do not mind repaired specimens for my own collection, in fact, all specimens that I have repaired are in our own collection. I have never sold a repaired specimen (not to say I will never). As one gentleman noted, we (over 50's) have all somehow been repaired. A major problem with repairing comes when the main crystal is fitted the wrong way round or even worse, on a foreign matrix. Honesty is a rare element, far harder to find than the rarest of minerals! I have heard of local diggers that are also getting clever and 'repairing' or should I say 'fixing' crystals to get a better price. Thank goodness, I have never experienced that yet.
I cannot wait to see the notes on repairing minerals that Louis friend is planning to post.

Tener un buen dia

[vicen]

Hi, I have been observing that the use of adhesives is quite commun, more than we think. I complitely agree with Alfredo and even I will add to his comment that the repairs should be done only when needed.
I have repaired quite a good number of minerals at the museum but only when needed for exhibitions or for resesearch. I normally use Paraloid B72, which I adore and know how to work with it. The adhesive is reversible with acetone, quite strong, and doesn't yellow. This adhesive has been used in the last 20 years in conservation and it is easy to use and no expensive.

[Riccardo Modanesi]

Hi to everybody!
According to Alfredo: I wonder why in Europe there are so few "repaired" minerals and in the US there are many more!
My opinion is based in two points:
i) it is useful to study repaired specimens as well, so that we can distinguish them from the "pure" specimens without needing a disclosure, as well as we do with synthetic or artificial materials (for example synthetic gemstones).
ii) however it is STRICTLY NECESSARY to have a full and complete disclosure about artificial treatments of minerals and gemstones, including repairing of a mineral! This is a treatment as well as heated amethysts which turned their colour into citrine or irradiated diamonds taking all of the colour you can imagine!
Greetings from Italy by Riccardo.

[Pierre Joubert]

[vicen]

Dear all,

Paraloid B-72 is being well studied in the last 20 years or so. I have included some files that can be of interest to you. Even if the articles are for fossils or archaeology, you can use the same techniques used and will help you to understand how the adhesive works.

There is a new article that will be published soon on SPNHC called: "Paraloid B72: Practical tips for the vertebrate fossil preparators" by A. Davidson and G. W. Brown, that will be of great help.

Hope it makes sense,
Vicen

[vicen]

Have a look at this article which has just been out at
https://www.preplounge.blogspot.com
(link normalized by FMF)

Davidson, A. and G. Brown. 2012. Paraloid B-72: Practical tips for the vertebrate fossil preparator. Collection Forum 26(1--2):99-119

Vicen

[rocknut]

I've got a lovely quartz with a small nick in the termination.

Would smoothing the abrasion look natural and does this type of repair fall into the same category as using glue to repair broken crystals?
In both cases the goal is to restore the mineral.

I'm not interested in selling the specimen and if I ever did I'd disclose the repair.

Thanks,

Jeff

[GneissWare]

Just my opinion....

Grinding a face to remove a nick is much worse that using glue to restore a crystal back onto a specimen. The first is an act of manufacturing, whereas the second is a restoration or repair. The first is not reversible, whereas the second activity is reversible.

Some dealers will use a colored epoxy to fill in chips on a crystal. There is nothing in my opinion wrong with this practice if (1) it remedies a flaw that is very distracting, (2) is fully disclosed, and (3) is reversible.