Hi,
This is not quite as simple a task as it may appear. A lot depends upon the nature of the rock and the sample available. If the rock is very distinctive, a visual examination may be all that is required, but I rather doubt that will be the case. If it is a piece of limestone or sandstone (as I would guess) then it may well require a thin section to be made (this is a small piece glued to a glass microscope slide and then ground down to 30 microns thickness, for examination under a microscope). Making the slide and getting it to the correct thickness, is a skilled business. Even then it may not be possible to say exactly what rock type it is; saying it is limestone or sandstone (for instance) is easy, saying which one is much more difficult as rocks can be quite varied and the sample size is bound to be small, so any error may be large. A lot may depend on knowing where the dial is situated and whether it has always been there, as it is unlikely that a piece of rock would be transpor ted large distances just to make a sundial. I think it is unlikely you will be able to tie it down with any real certainty. There are no absolute determinative tests to determine what exactly rock type it is; it is all a question of mineral content and amount, but as I said that can be very varied over the length of a stratum of rock, even though it is the same rock and even the same bed! If it is a limestone and contains any kind of determinative fossil (but it will probably be in fragments, so not easy to look at) it may be possible to say roughly what age it is and thus to determine where deposits of that age are found. But the chances of this being the case are highly remote as most limestone simply contains crushed fragments of typical fossils of the period. The obvious place to ask is the Natural History Museum in London which nominally runs a public ID service. I know because this is just the sort of public enquiry I used to deal with as a geologist there. However, I doubt now that they will want to do it as there are no benefits from doing so and there is a lot of work involved. Also there are not the staff there now to deal with these types of enquiry. If they do, there will be a charge for making a section (if it is needed) and for the identification (if it is possible), and it won't be quick. You are welcome to give it a try, but don't say I suggested it! I hope this helps Regards peter ________________________________ From: sundial [[email protected]] on behalf of David Brown [[email protected]] Sent: 03 November 2016 05:44 To: Frank Evans Cc: Sundial Subject: Re: STONE SUNDIAL Dennis, you could try the Stone Federation whose address is www.stonefed.org.uk<http://www.stonefed.org.uk> David Brown Sent from my iPad On 2 Nov 2016, at 12:06, Frank Evans <[email protected]<mailto:[email protected]>> wrote: >From my son-in-law, a geologist. Frank 55N 1W -------- Forwarded Message -------- Subject: Re: Fwd: STONE SUNDIAL Date: Tue, 1 Nov 2016 22:37:18 +0000 From: Bob Downie <[email protected]><mailto:[email protected]> Reply-To: [email protected]<mailto:[email protected]> To: Frank Evans <[email protected]><mailto:[email protected]> Hi Frank A possible yes. I believe the Forensic Soil Science group at James Hutton Institute in Dundee has a geochemical database for many rocks and soils in the UK. They could possibly help but almost certainly at a price. Other than that many university departments could possibly help if the rock-type is local/distinctive. Cheers Bob On 01/11/16 21:27, Frank Evans wrote: Begin forwarded message: Interest only. Frank From: Dennis Cowan <[email protected]<mailto:[email protected]>> Date: 1 November 2016 at 20:09:14 GMT To: Sundial List <[email protected]<mailto:[email protected]>> Subject: STONE SUNDIAL Does anyone know of a facility in the UK where a piece of stone from a sundial can be sent to try to establish where the stone originated from? Dennis Cowan Sent from my Mobile --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial
