Diamond selector II (6 month guarantee)

Summary

This is a diamond-only tester, it does not test for any other stones; this is the simplest type of tester, the manmade stone Moissanite will register as diamond. 

All Diamond Selector testers look the same but the quality of the construction and the components varies. This is the cheapest diamond tester that is actually useable. Better quality than super-cheap testers you see on eBay and Amazon...but it's still one of the cheapest.  Guarantee against breakdown is 6 months. Be aware that this is not the best as regards accuracy (i.e. how often you will get a correct reading).

• Just right for anyone who shudders at the thought of spending £79.00 on a decent tester, let alone £350.00
• Maybe OK for those who say, "I will use it so rarely that want to spend as little as possible" 
• Standard format, nearly everyone who has used a diamond tester is familiar with how to use this one
• Adjustable sensitivity, so you can (within limits) use it in cold conditions
• It does not test for Moissanite (a manmade stone that is not diamond): Moissanite shows up as diamond on this tester.
• Guarantee: 6 months

See also, everything you need to know about testing diamonds in the Guide to buying diamond testers. 

Operation

Turn it on, wait about 30 seconds for it to warm up, carefully set the sensitivity according to the chart on the tester (this can be fiddly), place tip in the centre of the stone.

Providing you have set the sensitivity correctly, on diamond the row of LED lights shoot up to the end and it bleeps; on most other stones nothing at all happens.  The lights can move slightly on ruby and sapphire especially if they are large but this does not 'prove' you have a ruby or sapphire, any large very cold stones will light up the row of LEDs (though if the sensitivity is set correctly, they shouldn't light up into the diamond range).

Technical

PHYSICAL

Size: 6¼"X1½"X¾" 155X38X20mm

Weight: 105g

Tests stones down to about 0.03ct (3pt) in size

Operating temperature: recommended between 18 and 27 degrees C (64 to 81 degrees F), not reliable at lower or higher temperatures. 

RESPONSE TIME

Warm-up time about 30 seconds

Testing time 2 or 3 seconds   

Warm-up time between tests anywhere from 3 to 8 seconds depending on the temperature

POWER

Power: one PP3 battery (supplied)

Battery life: un-tested, but possibly a few hundred tests

Auto-shut-off: none, i.e. if you forget to turn it off the battery goes flat

Low-battery indicator: none, if the lights fade or flash erratically, or if you get incorrect readings - try changing the battery. 

ACCESSORIES / PRESENTATION

Carrying case

Stone-holder

Poorly-written instructions

Limitations

This is a diamond-only tester, it will not test Moissanite, that means Moissanite will register 'diamond' (for other models see the ALTERNATIVES tab). 

We haven't tested this on thousands of stones (as we do with our expensive testers) but, generally, I would expect this quality of tester to give a correct result 70% to 80% of the time. All Moissanites will read 'diamond'.  

Disclaimer

All testers  must be used in conjunction with the user's skill, knowledge and experience. Under no circumstances shall QUICKTEST be liable for direct or indirect loss sustained in connection with any item. Nothing is 100% accurate, you must understand the limitations of any tester you buy. We also suggest you regularly test known samples to check for any obvious faults. Full support given for items you buy from QUICKTEST.

Alternatives

Please note, none of these testers will distinguish natural stones from synthetic stones. "Synthetic" is a scientific term meaning 'made by man in a factory/laboratory to the same formula found in nature'. The two are usually indistinguishable, synthetic diamond is diamond (read about synthetic diamond testers and see our ARI and ARETE models).

The testers below are to distinguish diamond from non-diamond (simulant/imitation).   

[1] All testers test loose stones but not all can test mounted (set in jewellery) stones.

[2] The probe / analogue meter will test mounted stones, the digital meter will only test loose stones.

[3] The probe / analogue meter: 17 stones; the digital meter: 40 stones.

[4] Skill and practice is required to use an optical refractometer, instructions are not included, see any textbook about gemmology…or the internet.