FMF - Friends of Minerals Forum, discussion and message board

[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.

[Tracy]

I was thinking the same thing. in one case you are restoring a specimen to what it once was, in the other you are altering the crystal from its original form.

- Tracy