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Quartz Wedge for Polariscope

Cannot find any for sale (and not interested in spending $75 if they were) and the plastic substitute also seems to be unavailable. I have lapidaries ALL OVER my town. Would Icelandic Spar work, it is quartz.

Hmmm, isn’t Icelandic Spar CALCITE?
Not Quartz?

I thought so too, but listing I saw in eBay (yes I know) said quartz and it was only $9, so either I am getting something that will work or a cheap display piece LOL

No, Icelandic spar will not work. It is double refractive, which means as the light enters the spar, it splits into two paths. You can see this easily by placing a clean piece of spar on a dot on a piece of paper. Looking thru the spar you will see two dots.

And yes, spar is calcite, a much softer stone.

If you need a wedge, grind one yourself from a scrap of water clear quartz on a flat lap. Not at all hard. Just takes a bit of time and effort. You can find optical quality quartz in most rock shops, or online sellers/ ebay.

According to Hanneman, you can use a piece of florist’s cellophane. If I recall correctly the in-out direction is along the long axis of the roll or cellophane, but it should be pretty easy to figure out. Also Hanneman suggests the top or side of a clear plastic box. These two should be easy to find and use. Yes, it is possible to grind a wedge from a piece of quartz, but it has to be rather thin and I think it is pretty complicated to do…there was an old Lapidary Journal article about doing it and I remember thinking it wasn’t something I wanted to mess with…

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LOL I am thinking that CRYSTAL in Chinese “literally” translates as Quartz, at least when using translation software.

No, nor me, from what I’ve read.

In order to fabricate the compensator, a rectangular slab of quartz approximately 15 × 35 millimetres in size is ground into a wedge with a thickness ranging between 0.1 and 0.25 millimetres from the thin to the thick dimensions.

If I understand it right, the crystal used needs to orientated right as well, too complicated for most places to do with ordinary lapidary hardware, much cheaper and easier to buy one, if you need one bad enough.