Just purchased a $100 refractometer

I just bought a refractometer from here:
Gemological Tools – NISupply.
Only $100. It comes in a softcase with a bottle of 1.80 RI fluid. It has an internal led light that has the yellow color like a sodium lamp. There is also a polarizing filter. I tested a piece of light amethyst that had a large table and got the expected reading of 1.54 to 1.55 that varied as I rotated the polarizing filter.

The RI fluid certainly does stink. I’ll have to remember to hold my breath when I put my face near the refractometer to read it.

Hi David,

Would not have thought to look at that site, until you posted it. I unfortunately paid a tad bit more for mine… 3x more … :slightly_frowning_face: :cry:

Ventilation is definitely important when using the RI fluid…



I have tested several faceted stones from my collection now. I have tested an amethyst, a couple of blue topaz and an emerald and I have found RIs within the expected ranges. The amethyst and topazes were multi-carat stones with tables wider than the refractometer’s lens and these gave me fairly sharp readings. With the smaller emerald I think I used to much RI fluid and was seeing an additional shadow when trying to read the RI.

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Sorry for the delay. I didn’t get notification that you had replied to this. That is great news that the refractometer seems to be working as expected. Sounds like you found a “keeper”. :grinning:

There has been a delay to my practice time on my refractometer. Just recently moved to new location, and unfortunately discovered that my original bottle of RI fluid had completely dried out. That was entirely my fault. The fluid bottle was not capped tightly enough and the fluid leaked out into the double-bagged and zip-lock sealed package. It is now a collection of crystals.

I haven’t found any information on how to reconstitute the crystals into liquid form. And I would question the quality of my effort in doing so, as part of the plastic wrap has dissolved. Pretty sure that will contaminate and change the R.I.

Have ordered a new batch. Hopefully, it will arrive here soon.