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Adhesives for use with mineral specimens, either to repair, stabilize or to mount your specimens is a very touchy subject. Many curators of collections and experts in the field abhor the use of any material foreign to the natural state of a mineral specimen. Yet very few mineral specimens are of museum grade or of such value that using an adhesive would hurt them. But the primary mantra or rule for using an adhesive on any mineral specimens is : | "Make sure it is reversible!"
And I'm not kidding about this - make sure the adhesive is reversible. There is nothing more frustrating then to watch a repair go bad, discover you used the wrong adhesive or applied so much it is destroying the look of the piece. There is also the case of reversing a repair for other reasons, especially if the piece needs to be tested. Whatever you decide to use, make sure there is always a method of reversing a repair and that that reversal method is also safe for the specimen. |  Two Basic Types of Adhesive
The most common types of adhesive use a solvent to suspend the adhesive, evaporating to "harden it." These solvent glues are actually my preferred method to do repairs. A solvent in the glue can be anything that can evaporate, including water, alcohol, acetone, toluene, etc. The one everyone is familiar with, white glue, uses water to keep the glue suspended.
The other type of adhesive uses a chemical reaction or temperature (energy) curing to harden the glue. These are the epoxy, superglue and thermoplastic types. Many variations exist of this type of adhesive and most are a specilty application. Exact formulation and amounts are mandatory to obtain good results. Most everyone is familiar with the two part expoxy type and the superglues. Still, most of the commercially availble brands are of very poor quality and should be avoided at all costs. Most cause probnlems which are difficult to reverse. | Mineral Tack -
 Another adhesive in common use with mineral collectors is the putty like material, actually a plastic based putty) to mount a specimen in boxes or upon a stand. Two types are commonly in use, the tack in blue and another in white. The blue type can still be found at hardware and office supply stores. Often under a different brand name, this photo is of just one brand still available. It is no longer sold through most mineral shop sources and has gone into disfavor amoung collectors.
The white colored material is called "Mineral Tack" and has excellent qualities. Upper most of these is that it will not stain a specimen, will not harden, remains "tacky" and holds specimens securely in most cases.
To remove mineral tack -
A tip to remove mineral tack that is stuck to a specimen is to wad up a ball of the same material and dab it onto the material stuck to you mineral. Keep dabbing at the mineral and the wad will pick up the mineral tack even in the crevices.
Although this article will not detail the mineral tacks, make sure you use one of these two brands mentioned above and not other types of putty or caulking material. Most use an oil to keep them pliable and this will damage your specimens and this damage usually cannot be removed. |
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