- Mizar M24 - detail / review
£125.00 including VAT, buy now

- GemOro AuRacle AGT1 - review
[now sold out...and discontinued]

- GemOro AuRacle AGT3 - review
£559.00 including VAT
, buy now

- GemOro AuRacle AGT BLUE - review
Best price £439.00 including VAT, buy now

- GemOro AuRacle AGT2 - review
[now sold out...and discontinued]

Related articles



Article: Everything you need to know about gold testing (article on web)

Video AGT1 - for previous (discontinued) model, AGT1 DELUXE, but the actual testing procedure is very similar to their other models

Instruction Manual AGT1 PLUS (pdf). Instruction Manual AGT3 (pdf)



Go to TOP for prices

IN the following summary
- by 'very accurate' I mean that it should be correct to the actual carat displayed, e.g. if it reads 9ct it should be 9ct.
- by 'reasonably accurate' I mean it should be correct plus or minus 1ct, e.g. if it reads 18ct, it's probably 18ct but it might be 17ct, it might be 19ct.
- by "somewhat approximate" I mean it should be accurate plus or minus 2ct, e.g. if it reads 22ct, it might be 22ct, it might be 20ct, it might be 24ct.
- by "not accurate" I mean that an item reading 18ct might really be 16ct, might really be 24ct.

Mizar M24: somewhat approximate for testing 9ct to 14ct, not accurate for testing 16ct to 24ct.

GemOro AuRACLE AGT1, very accurate for 9ct to about 12ct; reasonably accurate for 12ct to about 14ct; somewhat approximate between 14ct and 24ct.

GemOro AuRACLE models AGT2, AGT3 and AGT Blue are very accurate at 9ct to about 14ct; reasonably accurate at 14ct to 18ct; somewhat approximate between 18ct and 24ct.

We have had a few customers return these (in the first 14 days) when they discover that they can't tell the difference (for instance) between 18ct and 20ct, or between 20ct and 22ct. These testers are not accurate when testing high carat. They will give a reading to the nearest 1ct but the reading will not be accurate. If you need to test high-carat accurately, use either acids or XRF (see below). If you find an electronic tester (for under £1,000.00) which is claimed to be more accurate than the AGT2 / AGT3 / AGT Blue, please let me know because I've never seen one.



If you want to know if your items are about 9ct, or about 14ct, or possibly better than 14ct, then the Mizar M24 might suffice, but it's fiddly to use and it uses a strong acid as a contact fluid which corrodes the machine if you're not careful (not covered by the guarantee!).

if you really don't buy much gold, are working to a tight budget, and have the patience to 'get the feel' of the readings, then an AGT1 model might be OK once you have learnt to interpret the readings, and providing you never rely on the readings for high carats. Our experience was that most customers didn't have the patience to 'get the feel' of the readings, and they didn't find it accurate enough, and we have discontinued this model.

Most scrap dealers use either the
AGT BLUE that connects to any phone with a free app. (see below for review); or the AGT3, the best stand-alone machine (see below for review).

One dealer covers all eventualities: away from customers she uses an AGT as a very quick and easy way of sorting the scrap - then re-tests, with acid, high carat (or anything unusual that is giving inconsistent readings on the AGT).
In front
of customers, she always uses acids because they are more accurate and consistent in their reactions.

If you are happy with the limitations of these electronic testers, as described below, you will be pleased.
If you want consistent and accurate readings up to 24ct you will have to spend upwards of £12,000.00 on an XRF machine...or use acids.

If anyone tells you (of an electronic tester for under £1,000.00) that they are more accurate than I have described, send me the details and I will investigate for you.

So what else can I recommend?

There is a new make which I have put through its paces, testing many dozens of samples. It is the most beautifully-designed tester I have seen, and by far the easiest to use. However, it is hopelessly inaccurate for testing above 18ct. I am selling the samples at a fraction of the retail price, but I am selling this as a tester for 9ct to 18ct only.

WHEN I find a new electronic tester that I consider accurate and robust, the review will appear on these pages, and IF you buy one from us you will know exactly how well it works and the level of support you will get from us - so bookmark this page!



Buy now


- very cheap
- very simple, a light for each carat
- Mizar make a few models, this is by far the best of them


- it's not accurate.
- the acid contact fluid will dissolve the sensor if it is not cleaned meticulously after every use. Once the sensor is corroded, the tester is beyond repair.
- they provide a standard eraser to clean the gold, this is not good enough to remove plating, so you will get a false readings on plated items.
- you need good eyesight and a steady hand to place the test-item into the tiny well of liquid (that must fill with acid) without touching the sensor.



Go to TOP for prices

How do the AGT testers compare with 'cheapie' (e.g. Mizar) electronic gold testers?

The AGT1 has a row of 32 LED lights between 6ct and about 24ct, so it's easy to judge which carat is lighting up - but it is a matter of judgment, the lights are hesitant to settle. Nevertheless once you've learnt to interpret the lights, it's much more accurate than the Mizar.

The AGT3 and AGT BLUE models have a digital display, so you can't compare "numbers of lights" - but they are cleverly designed with a fast mode' for very quick approximate tests, or an "enhanced mode" for accurate testing.

"Cheapie" electronic gold testers (such as Mizar) use an acid contact fluid. The contact fluid in all of the AGT testers is a harmless salt solution.

How do the AGT testers compare with XRF?

XRF testers cost between £12,000.00 and £50,000.00 and display a chemical breakdown of the metal, listing not only the percentage of gold but also the percentage of all the other metals. So XRF is better. In fact, there is simply no comparison. For instance, an XRF tester might tell you that the gold content of an item is 76.183%, an AGT tester will tell you it's about 18ct (75%) but maybe a little less, maybe a little more, with no clues as to what the remaining 25% of metals might be.

How do the AGT testers compare with acid testers, for safety?

AGT testers use a probe containing a simple salt solution, most other electronic gold testers use a contact fluid made of acid.

XRF testers use x-rays, when used properly they present no risk, but I do see them used by dealers who hold items in their hands whilst testing, and so give themselves a dose of radiation. several times per day. They will get cancer. As with acids, XRF is safe if used properly.

How do AGT testers compare for consumables?

An AGT probe will last for thousands of tests (the manufacturers say 5000, some of our users say it's less than 1000 - providing you remember to put the cap on tightly) - and a replacement probe is not expensive.

A replacement bottle of acid for an acid tester lasts for 100 to 150 tests and costs about £10.00.

A replacement bottle for a Mizar M24 costs £27.50 and lasts about 50 tests.

When an XRF tube wears out, a new one will cost from £2000.00. Plus a service, plus any repairs that are needed, plus VAT...plan on a minimum of £3000.00.

How do AGT testers compare for repairs?

If an AGT breaks down during the guarantee period it has to go back to the manufacturers, Gemoro, in the USA, they insist on repairing these, they will not exchange them unless there was a fault the first time it was used and it still looks like new. If it breaks down out the guarantee period, we can send it back to the USA for a quote for repair if you wish to pay the postage to the USA (£20.00) + the postage Gemoro charge to return it but there's no guarantee that a repair is econometrically viable (Gemoro charge £73.50 for the return postage alone). When all goes well, it takes 4 to 6 weeks for a repair or replacement.

An M24 is not worth repairing.

XRF is likely to cost two or three thousand pounds to repair, we don't sell or service these so I have no experience of their service.

An acid tester cannot 'break down', you simply buy a new bottle of acid.

How do the AGT testers compare for speed of testing?

AGT1 testers are faster to use than acids.

AGT3 and AGT BLUE testers, when set to enhanced mode are about the same speed as acids, though there's not a lot in it, and it depends on the carat. The quick mode is very fast (much faster than acids) but isn't accurate.

XRF also has quick and enhanced modes. On enhanced, XRF is slower than both AGTs and acids (the videos always show them in quick mode!)

Which tester is the 'least destructive'?

All electronic testers, from £100.00 to £50,000.00, will only test the surface of an item (though XRF can test through very thin plating, and the latest NITON brands can detect some types of plating) - so you must file the surface first, so that you are testing underneath any plating. The same applies with acids, you must file the surface first. There is no tester that requires 'less' filing or 'more' filing. You must find a discrete place to file, you use a fine needle-file. A file is included with every AGT tester and with every acid tester.

How do the AGT testers compare for testing silver, platinum and Palladium?

The AGT cannot test for silver - acids can, XRF can.

The AGT can test for platinum, but Palladium reads as platinum too, and usually the platinum reading flips between "platinum" and "not gold".

Both acid testers and XRF testers can test for silver, platinum, Palladium and steel.

How do the AGT testers compare for 'calibration'

Every gold tester has to be 'checked against' known samples.

If you haven't used a bottle of acid for some time (they get weaker over the weeks and months) you must check it against known samples, any hallmarked gold will suffice.

If you are suspicious of the results of an XRF tester you must send it back to your supplier for service and calibration.

The AGT testers need to be checked against known samples too, you press some buttons, the electronics 'calibrate' the machine to the sample. You will need to do this whenever you turn the machine on, and every few tests, otherwise you will get incorrect readings.



Go to TOP for prices

Now discontinued

Please see above to find out how the GemOro AuRACLE testers (all models) compare with other gold testers.

Not all AGT1s are the same.

The original (AGT1) model

In its day this was the best on the market, nowadays it's considered very 'basic'.


Very good, fast and accurate for testing low-carat but not accurate for testing high carat (above 18ct). Quite OK once you've got the 'feel' for how the lights shoot up, then keep going up, then slowly go down, and usually settle on a reading...


...but not everyone has the patience to spend time 'getting the feel' - many spend ten or twenty minutes with it, then give up. Shop staff who don't get proper training, don't have time to 'get the feel' or are under pressure in a busy shop - they will never get any meaningful readings.

Each time you switch it on you must calibrate against the 14ct calibration sample; sometimes it doesn't work and you have to calibrate it a second (or third) time, then you must 'charge' the probe by carrying out a few 'dummy' tests before getting a reliable reading, and all of this takes 1 or 2 minutes.

Each time you switch it on you must 'charge' the probe by carrying out a few 'dummy' tests, and it's wise to do this whenever you start to get inaccurate readings.

Every few days (if you're unlucky) or every few weeks (if you're lucky) it has a nervous breakdown and won't work at all, it is not 'broken', you can fix it by calibrating it 6 or 7 times in succession, it's not difficult to do but it is frustrating, especially if you have a queue of customers.

If you have plenty of time and plenty of patience it's OK. For any serious trader I'd give this one a miss.

Not at all accurate at testing above 18ct, see above.

The (AGT1 Deluxe)

Generally, see above for the pros and cons of all AGT1 testers.

Specifically, compared with the AGT1 (original):

- calibration usually works first time, it has nervous breakdowns less often, it 'feels' nicer to use (more responsive), altogether it's faster to use. You still have to 'charge' the probe by carrying out a few 'dummy' tests before getting a reliable reading. It's not as frustrating to use as the original AGT1 but there will still be times when calibration doesn't work the first time and you have to calibrate it 3 or 4 times in succession. You still need to spend time 'getting the feel' of the readings.

- larger carrying box, fitted-out to hold all the accessories. I notice that there's an American style of presentation: the larger the box the better the perceived value. Here in the UK it's more of a selling feature if everything is small and easy to carry around.


Generally, see above for the pros and cons of all AGT1 testers.

Apart from that, it's similar to the AGT1 Deluxe, with the following improvements:

- the manufacturers say that the electronics were re-designed.

- not essential to 'charge' the probe before use...but it's still a good idea to do so (say the manufacturers).


Buy now

Please see above to find out how the GemOro AuRACLE testers (all models) compare with other gold testers.


Instead of a row of LED lights it has a digital display. It is not just having a digital display that makes the difference, it's the way they have computerised the on-display instructions. It tells you when to calibrate; when testing, it tells you to wait a few seconds and it tells you when the reading has stabalised and the test is complete; it tells you if the test has failed and you need to try again. All of this removes the element of 'judgment' that you need with the AGT1 models (judging when the row of LED lights have stabalised and you have a valid reading).

There are two modes of testing. A 'quick' test will indicate the approximate carat (e.g. 10ct [because it's American], 14ct, 18ct or 22ct); a detailed test will give a reading to the nearest 1ct. (i.e. it gives a reading to the nearest 1ct, that does not mean it is accurate to the nearest 1ct).


The 'prompts' on the screen are very good reminders, so that you don't forget what to do, but you do have to start by reading the instruction manual very carefully. Many customers don't bother with the instruction manual, then they bombard us with questions about how to use it. It is not magic, you don't just switch it on and touch your item with the probe, you do have to put some effort into learning how to use it. It is a hundred times easier than earlier models, but you must read the instructions (see the instruction manual).

The instruction manual is beautifully illustrated but very badly written, you might have to read it several times.

Not accurate at testing above 18ct. For instance, if an item reads "22ct" the best you could say is, "This item is about 22ct but it could be about 20ct or it could be about 24ct". It will still give a reading to the nearest 1ct, but that doesn't mean it's accurate.


Buy now

This is the same as the AGT2 below, but has the advantage that it connects to your phone using blue tooth, so you don't have to connect a wire. The app. is also able to connect to the internet to find the price of gold. Works with Apple iOS; also works with Android mobile devices with Low Energy Blue tooth capability (requires Lollipop version OS or newer).


- It's the smallest, neatest, fastest electronic gold tester
- Blue tooth and internet connectivity


- it's expensive compared with the old, discontinued, AGT1 and AGT2 models.
- you need to connect it to a phone, it's not a 'stand-alone'
- you might find, when you get new phone, that the app. no longer works and you will have to wait for the manufacturers to release an update.
- at some time in the future the app will no longer be updated and you will not be able to use the machine. This applies to any product that uses an app.

We didn't start selling these until late 2016 and haven't really sold enough to gauge the reliability. So far (Autumn 2017) I'm impressed, nobody had telephoned to ask us how to use it, nobody has complained about its accuracy. A few customers said it stopped working and they had to re-install the app, then it worked fine. I like products that work and are hassle-free (for me as well as the customer), I like this one!


Auracle AGT2 electronic gold tester


Please see above to find out how the GemOro AuRACLE testers (all models) compare with other gold testers.

The GemOro AuRACLE AGT2 consists of a probe, a testing plate, a small box of electronics (which is not shown in the manufacturers pictures), connecting leads, and a large-ish fitted case. You connect it to a 'mobile device' (smartphone, tablet, netbook etc.) so you already have most of the hardware.

It's basically the same as the AGT3, so see above for the main PROS and CONS.

There are two versions, one for Apple and one for Android.



- display can be set to 'digital' (see photo) or 'analogue' (displays a dial with a pointer) - 'analogue' display shows 9ct in addition to 10K ("carat" is UK spelling, "karat" is US spelling).


- you must plug it into a USB port (not all notebooks have USB ports)
- you must study the instruction book, the instructions are not self-explanatory from the app, many customers don't bother and get into an awful muddle
- you might find, when you get new phone, that the app. no longer works and you will have to wait for the manufacturers to release an update.
- at some time in the future the app will no longer be updated and you will not be able to use the machine. This applies to any product that uses an app.
- unlike Apple, Android isn't guaranteed to work with every Android device and there have been problems with it not working on new phones.
In 2015 the manufacturers advised:

Android Version requires the following specifications: Honeycomb 3.1 or higher, and USB host (or USB On-The-Go, “USB OTG”) support, and a touch screen with a width at least 320dp. It does not work with the Samsung Galaxy S2, Motorola Razr, Droid Bionic, and all HTC devices that are not compatible with USB OTG (Please check your hardware manufacturer’s documentation to ensure support for USB host or USB OTG).



- works with any Apple device.
- display can be set to 'digital' (see photo) or 'analogue' (displays a dial with a pointer) - 'analogue' display shows 9ct in addition to 10K ("carat" is UK spelling, "karat" is American spelling)

- same as the Android version, above, though generally Apple apps are more reliable than Android apps.


Methods of testing gold (and other precious metals)

More methods of testing gold (and other precious metals)

Acid tests, what he various testing kits do

Testing white metals

Testing gold, specific gravity method





QUICKTEST, Watford, WD18 8PH, Tel. 01923 220206, email info(at)quicktest.co.uk