Ade Advanced OpticsGL500 Gemological Gemstone Gem Refractometer Built-in Light, Aluminum Body with Optic Lens

After getting some duds in this price range, I was pleased to get this refractometer. It gives a good clear reading and feels like a quality instrument. This style is easier for me to use on faceted gems than the more $ GIA model. You need to order the RI fluid separately (expect to spend around $80 for the good stuff). My only complaint is that you better have extra batteries on hand in case you accidently leave the internal light on (there is a side push button), as there is no way to use an external light source. And the directions for the batteries and battery compartment don't match this instrument, but you can easily figure it out. Other than that, this is great quality and value.

It seems that everyone’s experience buying this product is different. Mine came with a hard case but not a soft case and also i didn’t get any RI fluid which is pretty irritating because i can’t use it until i get the fluid. Also the shipping took a long time, and it was delayed on top of that.

Works great and is easy to read.

I've been really impressed with the quality of this refractometer. I was concerned that it wouldn't be accurate, but it ended up being great. Having said that, it didn't come with any refractometer oil, which it was supposed to.So I'm going to give it three stars as it's taking me a long time to track that down. But realistically, this is a five star quality product. They just need to QC their packaging better. It's heavy cast iron, and I verified that the readings are indeed accurate using calibration stones. I wish I could give it five stars, but had to track down and wait for refractometer oil.

What I liked about this product is that it feels very high quality it came from the United States. Oregon. It also came with an insightful Direction pamphlet and a refractive index chart thanks you guys

Let me get a couple of negatives out of the way up front. First, it takes three button style batteries, which are not included... no biggie, but these are not a type of battery I keep on hand or use for anything other equipment.Second, the bottle of refractive oil had seeped out into the case and the cap on the bottle had completely corroded. Thankfully, the refractor itself was enclosed in a zip-lock bag and wasn’t damaged.The description says it comes with both hard and soft cases, but I only received the hard case.The refractor has a nice solid feel, and if taken care of should be very durable. Operation is simple... no learning curve required. We compared the accuracy against a more expensive unit one of my relatives has, and the readings produced by the two units was very close.The refractor itself is a nice little unit for the price, as professional units will cost many times the price of this one... so this is a bargain.

I like this one. Better than my old one. Works well.

When you open this thing up you definitely get the impression of a quality equipment. This is a well-made precision device and it’s kind of built like a tank so you get the impression that it will last a long time. It also comes with the case thank God for that because so many devices like this leave it up to the purchaser to find a way to protect a precision device and you never do better than a custom fitted case.Phone though has a bit of a foible. It uses very odd LR 44 batteries so you’re gonna need to get some of those because it didn’t include them. The battery compartment is extremely difficult to load and close. I’ve done tons of these and it took me about 25 minutes to get the batteries in. The aluminum screw cap has very tight tolerances and the batteries fit just barely so you’re constantly having to press on the lid and align it correctly and it’s not easy. It’s not like you have to do this often but I was definitely irritated by the time I got this thing closed up. So what’s a good test for this?I will note this is a prism refractometer so we can only measure gems who’s index is lower than the prism. That means gems like diamonds iand mossanite will not work in here.Then I realize that refractive index depends on the wavelength of light and it didn’t let me know what the wave length of the light was. 589.3nm Is the standard but 632.8 is also used. They will determine that it does use 589. So I put a piece of quartz in there with an expected index of refraction of 1.4585. My result was 1.46 is about as good as my eyes are capable of so I am convinced as to the device’s accuracy.Considering when some of these cost, I have to consider this device a huge bargain.