[Stepan]

Hello, I am using Polarizing light microscopy to measure refractive indexes of minerals. The procedure is like on this training video: http://www.youtube.com/watch?v=Q4QAwAAapZw.

Does anybody know where I can buy calibrated refractive oils in the range nD=1.55-1.70

[rjb]

Stepan,

The only manufacturer that I know of is Cargille http://www.cargille.com/refractivestandards.shtml who produce a range of RI oils of various grade and price... They're not cheap; a decent set costing around £1000+. Out of curiosity, what level of accuracy do you need as there might be a better option for RI determination...

Kind Regards

R

[Stepan]

Thank you Rib. I know Cargille. I would like to find either another supplier, or recipes for immersion oils. With recipe, I can blend them myself and calibrate for nD25.  I need only 4 RI's which are commonly used for asbestos testing: 1.550, 1.605, 1.630, 1.780, and 1.700. 3 decimal point accuracy is plenty for my application, but the trick is - they must have 6-12 month shelf life (essentially nonvolatile and chemically stable)

[rjb]

Stepan,

An alternative supplier would be McCrone (http://www.mccronemicroscopes.com/store/catalog.asp?item=231&category_id=72), who produce an immersion oils kit specifically for asbestos testing. Cost is $205, which I think is pretty reasonable.

If you're set on making up your own RI liquids, you may like to consider the following link, which might be of interest... http://www.rsc.org/delivery/_ArticleLinking/DisplayHTMLArticleforfree.cfmJournalCode=NJ&Year=2006&ManuscriptID=b513451j&Iss=3. Alternatively, if you have access to a hotstage, you may want to consider using a hotstage method using a just one or two oils.

Kind Regards

R

[Stepan]

Thank you RJB. Based on the image, MccCrone re-sells Cargille Lab product. You are right, the price is better than from the Cargille lab themselves when you buy it directly.

Your second link from RCS did not work from my PC, likely because I do not have subscription with them. Can you please email me the file on sreut(at)labconserv(dot)com ?

Thank you

[Stepan]

I received the article. Thanks a lot. This is a beauty.