mounting fragile specimens

I have been pondering how best to mount specimens that I can not easily glue to a mount or use tack. I am currently working on a sample of dundasite and it is very crumbly. My thought is to try using epoxy by taking a small drop of mix and putting it on some teflon plumbers tape then set the mineral on the drop. When it hardens I should have a good base that holds the mineral together. Any suggestions?

Roy

Fossil collectors commonly use consolidants when prepping fragile fossils; perhaps the same approach would work here. Unfortunately, some of these would likely be all too visible if used on mineral specimens for micromounts; nevertheless, it might be worth looking at some of the materials used for fragile fossils. Google on "fossil preparation" and go to the site for the Florida Museum of Natural History. The discussion of different materials found there is very useful. Epoxy is generally considered too irreversible to be recommended. Very thin superglue can work well if the sample is sufficiently porous to draw in the liquid by capillary action. It's a little easier to remove than epoxy, and it won't stick to teflon.

Some fixative sprays used for art work might work if you don't blow the specimen into the next county. Fixative sprays can have a pretty inconspicuous matte finish. Some fixative might be sprayed into a small cup, and then gently applied with a small brush to the bottom of the specimen. After consolidation, perhaps the specimen could be mounted conventionally.

You might also try a polystyrene cement (i.e., model airplane cement) thinned down with acetone as a consolidant. That way, you could easily remove excess with more acetone.

Let us all know what finally looked promising.

I don't have any specific suggestions, but be very careful with epoxies. Some of them have high surface tension and will creep (wet) the specimen and ruin it. Fairly viscous and gel glues would be best for forming a supporting base. If you can get some of it, sheets of Aclar are not wetted by epoxies and are a lot easier to use than Teflon tape (although they are a bit more expensive).

Henry

my suggestion is to flip the specimen and put a drop of Elmer's school glue on it and let it dry upside down. Then put some elmers on the intended receiving surface and the original hardened glue will give you a non crumbly contact surface which will better help your specimen to not only adhere, but to remain in one piece. I DO NOT glue to boxes any more. The contact is too rigid. Instead I buy precut black paper liners and then either glue a cork or mounting piece to the paper or the specimens directly to the paper. This ultimately gives you more flexibility for future handling of the specimen and allows some flex if the box is dropped or knocked over . Elmers, being totally water soluble and drying to a clear state, still makes it useable for me.

Here is how I mount my the REALLY tiny specimens.

I take a 4 millimetre plexiglass kind of plastic, cut it in square pieces and bore 2,5 millimetre holes into them. Then I place the grain/tiny or fragile specimen into the depression in the square plastic and glue a mica-thin, precut glass square over the hole. (The glass square is the same kind that is used in laboratories in hospitals). the specimen is lying loose in the depression. It is also possible to put a TINY mass of mineral tack in the bottom of the depression and orient the specimen on the tack. When mounting my specimens in this way I do not destroy the tiny specimens with any glue.

I have included some photos to better illustrate how this mounting style is done.

For many years I wrote the mineral name, locality, etc., with Rotring etching ink on my boxes. My supply of this very useful ink is very limited, so now I write only the mineral name and registration number with the ink. I now write the mineral name and locality with size 8 font on my computer, and print this information on a piece of paper. This paper label is glued on the bottom of the box.

I do not want to use self adhesive labels on my boxes because there is a big chance that such labels will fall off the box in X nuber of years from now. I do not want to have 6000 micromounts and 6000 loose labels.

I have for some time tried to find a permanent marking pen to use for the text on plastic boxes. Some brands are clearly better that other, but I have found none so far where the written text can withstand normal handling. Do you know a good brand of permanent pens suitable for writing on microboxes?

OT. I am intrigued by your mounting method. It appears that you have only drilled with the tip of the twist-drill, making a depression rather than a through-hole. Am I correct?

As to your lettering problem: have you tried lightly sanding the surface of the plastic and then using India ink?

Just for info, if you are looking for the glass sheets; they are known as " cover slips" to lab suppliers.

Tim

Yes, Mr Peck, you are right. I have only drilled a depression with the tip of the twist-drill.

Your suggestion of sanding the surface of the box before writing on the plastic was very good. When I covered the writen text with a thin, protective layer of glue, the text could withstand a lot of handling. Unprotected however, it was easy to remove the written text. I also tried to write on a sanded surface with a felt tip pen, and this text was much more difficult to remove with my fingers. I was not able to remove the written text completely but it became very transparent. But I do not like the transparent look of the text written with a felt-tip pen - the deep black letters written with the Higgins ink is much nicer I think. This will solve my writing problems on plastic boxes.

I use icing sugar to glue down really fragile specimens. You dissolve it in hot water and apply it warm to get it to harden faster. Specimens can be easily remove by placing them in warm water. However for really tiny samples I have found double sided tape works. If you want to be able to remove a sample later I have used the back of a postage stamp or envelope edge that you need to wet.

Howdy All,

I've attached a pic of a Dundasite and Crocoite that has been mounted for competition; it is sitting on the head of a dressmakers pin, glued with 'Weldbond' pva glue. (Sorry it is only a quick snapshot)

This glue is water soluble, and although it will take some time to break its bond when soaked in warm water, it will come off. It also dries clear and retains some flexibility for the life of the mount, helping to make sure it is resistant to knocks etc. the pin is placed into a piece of styrofoam with a piece of black art card on top for aesthetics.

So far with several hundred mounts like this with both fragile and very small specimens, I have only had 3 or 4 lose grip and come of their mounts. This includes shipping them overseas!
Hope this might help some.

Cheers Mark.

Hi Mark. If you didn't already know, that's a Kapi mine specimen. Regards, Steve

Howdy Steve,

Thanks for that one, I thought it was, but it came to me just with a label of Dundas.
I will make sure of the correct label now. One of my pet hates is lack of proper locality info on specimens, I believe you can always test and re-test a specimen to id it, but you can almost never re-label a location!


While I think of it, do you think this one is correct?
I would have said Platt Prospect

[www.mindat.org]

Cheers Mark.



Edited 1 time(s). Last edit at 11/03/2009 11:08AM by Mark Willoughby.

Correct Mark

Ralph

Absolutely Mark