SAMPLE PREPARATION DECISION TREE
[You need to top-mount mineral standards in your thin-section (or epoxy round).]
Note: this is a risky procedure for thin-sections because it is very easy to shatter your sample during drilling or polish through the sample during the re-polishing step. Proceed with caution!
Use a dremel drill to drill a shallow hole (typically <1 mm in diameter) that is no deeper than the diameter of your standard grains (illustrative image, jpg). The location of this hole should be near (<3 mm from) the center of the analytical "sweet spot." Place 3-4 standard grains in the drill hole – you may need to drill multiple holes to accomodate 3-4 standard grains depending on their size. Fill hole(s) with WiscSIMS-approved epoxies [Buehler EpoxiCure® 2 epoxy resin (product number: 203430064), hardener (208185016) and release agent (208185016), and Struers EpoFix Resin (40200030) and Hardener (40200031)] and allow it to harden.
Most likely, the best thing to do next is to polish the thin-section (or epoxy mount). See the first link at the bottom of this page, but note it is targeted at polishing epoxy mounts.
If instead you have the means to have a thin-section (or epoxy mount) polished by conventional means, then you'll be almost finished. You'll just need to cut a 1-inch square from your polished thin-section with the target in the center, and either cut or grind the corners off to create a circular thin-section. Please label the round thin-section by engraving the back of the mount (or for an epoxy mount, by attaching a paper label with an approved epoxy). Magic markers should not be used as we may use ethanol to clean your sample.
This should leave you with a round, polished thin-section (or epoxy round) with the analytical target and mineral standard grains exposed within the "sweet spot." At this point, you could proceed to imaging before WiscSIMS analysis (second link below).
Next steps (leaving decision tree):
– Polishing your thin-section
Note that this page is written for polishing an epoxy mount, but the same principles apply. If you have a more appropriate method for finishing a thin-section, please skip ahead to the Imaging section of the outline.