The program I referred to is Gemology Tools Professional, it is $59.95 for the download. Just google it. You input whatever data you have (dichroism, SG, hardness, RI, UV response, whatever) and it gives you one or more possibilities. Runs in Windows. If you get more than one possibility, you can decide from there what tests to do next to eliminate all but one. I do not have this software myself…haven’t needed it yet, but I have seen it in operation, and it works very well. Does not produce results which you could not get from your books, internet research, etc., but it is quicker, esp. if you don’t have all of gemology at your fingertips. Not all that expensive when you consider the books that it replaces. -royjohn
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@royjohn the way around the monitor variability comes from photography. I’m also a photographer and have been color correcting my monitors for about 15 years. The second thing you need to get is a color checker card. Its simply a card with a bunch of precise colors on it including black and white. You can get a generic one or the datacolor passport (needs to be replaced every six months if it is heavily used) to color correct the images. Once you have color corrected the images and have color corrected your monitor the gemewizard will give you excellent and precise colors for your gemstones.
I already happen to have these two things. The monitor calibration tools run about 200-300 us dollars and the color checker can run from 50 to about 150 usd depending on where you buy it, how much tax is and how much shipping costs.
Unfortunately, I just upgraded to the Mac M1 chip and now my monitor calibration device is no longer compatible with my Mac and I have to wait for a new version to become available here. I also have a secondary problem that I am using a curved monitor and I am unsure about whether the monitor calibration tool will run on the new monitor. I have therefore kept my old MacBook pro for determining the color of my gemstones since it is compatible with my Datacolor Spyder 4Pro.
The last thing you will need if using software like the gemewizzard is something like adobe lightroom or photoshop in order to color correct your photos of the gem in question.
I have a setup I use to take photos of my gemstones. I have a Fuji Xt4 with the Fuji XF 60mm f/2.4 on a tripod. I built my own light box using posterboard and photography LED lights to light the gemstone from almost 360 in order to get the best lighting possible. The LED lights are 5000K light and mimic natural daylight so I can take the photos at any time of the day or night and get consistent lighting. (if you have a setup like this that you will just have to create the color profile once as long as you use the same lights, camera and lens).
You can go the analog way and use a color book. GIA used to have a gemstone color kit that had about 1000 color samples (little plastic strips) you could place next to your gemstone and then compare the color. That kit used to cost about 1000 USD but is not considerably more expensive since I doubt there are many complete sets available for sale.
I’m not sure what other tools there are out there. I think I ran across a book with for color grading a few months ago but that book also cost about 1000 USD and the paper will fade over time.
I did a quick search while writing this reply and found this analog book set you can purchase here.
Once again I do not have any relationship, financial or otherwise, with any of the items I have stated in this post.
Thanks, Daniel for this very interesting explanation of how the GemEWizard can work. I do have the World of Color book and use it in valuation. It works pretty well but I have been unable to get to one of their training workshops in order to test whether I am doing well regarding my color grading…
The steps with the GemEWizard seem complicated and expensive. I need a calibration tool for the monitor and also the color card. I need a setup for taking a photo of my gem and have to work on the color temperature of the light on that as well as the light box. IDK if the colors on my monitor are linear in their variations or not. I have to color correct my photo, and who says I’m being accurate in doing that. So there are multiple steps where I am color judging my standards and my monitor and my stone, etc. A lot of room for error, if you ask me. I am not sold completely on the World of Color book, but at least if you assume that the book is printed accurately, you are looking at a standard and your stone. A little less room for error. We’re not left wondering whether the color sensors on the monitor are rendering blue or violet right, etc., etc. World of Color is $400, a one time charge. If course, you would need the annual subscription to the Gem Guide for actual valuation, that is ~$250/yr.
And, yes, you are right, you’d have a hard time finding a complete GIA Gemset at present. I think the GemDialog set of transparencies is still available and it will allow you to convert to various color notations through a key.
Not any really complete and fantastic alternative here, but a range of choices that are better than nothing. Thanks again for your input.
Very Best,
Roy
The monitor calibration tool will automatically calibrate your monitor. This depends on the quality of monitor and most monitors now have an excellent color gamut and should reproduce colors very well.
The data color monitor calibration tool:
You can buy a light tent for about 100 us dollars i think and it included natural daylight LEDs built into it so once you use the color checker you should have a way to automate and get very precise colors from your camera whether it’s a DSLR, a mirorless camera or s mobile phone as long as you put it through software that can use the camera profile you create for the specific camera and the light tent.
The color checker to build a camera profile:
Light tent:
Your total outlay would be about 300 USD for the tools, color checker and light tent. You would also pay about 10 USD a month for Lightroom to process the pictures. If you do this you will have a very high color fidelity that will allow you to get very consistent results with the gemeprice software.
Yes setting it up is a pain. Yes color correcting your monitor should be done at least once a week but preferably before color correcting your photos.
Yes it’s a hassle. But it’s a lot cheaper and more reliable than buying the book. The book will fade over time, especially if you use it under lots of light as the light will fade the white and any and all colors in the book.
I personally don’t see any better alternatives to doing this in order to get a very precise color grade for gemstones in general.
A mobile phone camera should be sufficient for this. If you want more precise color rendering i would suggest buying a Sony A6000 which can retail for about 300 USD or much less if you buy it used and a decent macro lens. A decent macro lens would be the 7artisand lens and that sells for about 100 USD. But like I said most mobile phone cameras should.be sufficient for this task so you don’t need to spend an additional 400 USD or more on camera gear.