Realcent.org

Sigma just announced a new PMV model that makes additional measurements to more thoroughly inspect coins and bullion.

The PMV PRO has two sensors built in, a large and a small, that measure the surface resistivity like the original PMV, but also measure the resistivity all the way through the item, and measure the thickness of the metal, even in plastic cards or slabs. Further, by entering the weight of the piece being tested, and the shape (round or rectangular), the PMV PRO can be used to check the density of the material. You enter the weight, measure the thickness with either the large or small sensor, and then use a reference point on the machine and lines on the screen to see if the piece is the expected size.

The PMV can optionally use two additional wands: a Refiners Wand to measure the surface resistivity of larger items, and a Microwand to measure items as small as 3mm. These wands measure the surface resistivity like the original PMV.

I had hoped to have a video and a thorough review ready for when they announced it, however UPS broke my demo unit in transit, so I am waiting on a replacement. In the meantime, you can read more about it on Sigma's website here:

http://sigmametalytics.com/purchase/pmv ... ption.html

And you can watch some factory videos here:

http://sigmametalytics.com/instructions ... ideos.html

I will post more once I have a functional unit in hand. If this performs the way I hope, there is a strong chance I'll run some kind of pre-order deal for BS and Realcent.

Very interesting! Does the unit cost a lot more then the original?

highroller4321 wrote:Very interesting! Does the unit cost a lot more then the original?

Street price will probably be around twice the current street price of an original PMV. The main unit has 4 sensors instead of 1 (a small and a large which each have a top and a bottom), plus a color LCD screen with a graphic interface.

Do they have examples of materials where the original fails with a false positive and the new one detects the fake?

I'm pretty happy with the measurement mode on the original, which I like almost better than the pass/fail mode, but maybe there are some sophisticated fakes that I'm missing.

68Camaro wrote:Do they have examples of materials where the original fails with a false positive and the new one detects the fake?

This is what I want to test. I have some carded gold bars that register as genuine. I'm thinking at the very least the thickness/dimension checking ability of the PMV PRO will be able to sniff those out. The through-metal reading may also differ enough from the surface reading to raise a red flag. I plan to do some side-by-side testing with the original and PRO units.

Not sure if I saw that right but the new one is $1600? That seems like a steep jump over the original.

I looked at the "fake samples demonstrated" video, and it left me uncertain about what it was doing. In the last example, 1/4 oz gold .9999, the diameter was way off. The PMV reading was in range, but the through thickness reading was slightly low 1.99 vs 2.14 - which is hard to do in a fake unless you are using copper or silver as one of the interior metals. Unfortunately, if someone is going to game the system by focusing on the PMV reading (ignoring physical dimensions), I believe (for gold, haven't thought through the other choices) it would also be quite possible to game the composite electrical resistivity not only in a surface reading but also a through the thickness reading. In this case they didn't try to match the entire response, but I think they could.

I think the solution is holistic - you have to consider all the data, including the weight and physical dimensions, as well as electromagnetic results.

Robarons wrote:Not sure if I saw that right but the new one is $1600? That seems like a steep jump over the original.

Agreed. I was hoping the price of these machines would go down over time (like practically all electronics).

68Camaro wrote:I think the solution is holistic - you have to consider all the data, including the weight and physical dimensions, as well as electromagnetic results.

Correct, which is why the PMV PRO integrates dimension (density) checking. Fakes can match the size and weight, OR they can match the resistivity, but there's no known way to fake both in the same piece. The biggest feature of the PMV PRO for me (having not actually tested it yet) is being able to measure the thickness of the metal while it is inside a card or slab. That enables much more thorough testing of carded and slabbed items without opening/destroying the packaging, which has been a big challenge thus far.

Robarons wrote:Not sure if I saw that right but the new one is $1600? That seems like a steep jump over the original.

It's not cheap, but the PMV PRO has four times as many sensors as the original and a much more complex operating system and display. I am guessing some used original PMVs will hit the market once the PROs start shipping, might be able to snag a deal on something that way.

PMV PRO List Prices
base unit - $1395
w/ one wand - $1520
w/ both wands - $1595

They will be available for less than that. I am still working out what I could offer them for, but I want to thoroughly evaluate/review one first.

I have a video uploading to YouTube right now, it will probably take a couple of hours with my slow connection at the office.

The two biggest concerns with the original PMV are pure copper testing as silver, and copper (or silver) alloys testing as gold. I have yet to see a silver-plated copper fake, but theoretically this could be done and would fool the PMV by itself. And there are already counterfeit gold bars (mostly the fractional bars in plastic cards) that read as gold. By using the thickness measuring and dimension checking features of the PRO, you can indeed distinguish copper from silver and copper alloys from gold, even when the resistivity values are the same. And typically the two resistivity values you get with the PRO will differ enough on a plated item to raise suspicion (the values should be very close to the same for a pure solid piece of metal).

You can of course also do this manually with calipers and a scale, which is what I have always recommended using in conjunction with the original PMV, however you have to remove the item from the capsule/card/slab and either need reference dimensions (such as those in the Fake Bullion Database) or must do the math to calculate the density and compare it to the known/reference value. The PMV PRO does all the calculating for you, so you get to use a visual interface instead of crunching numbers, and do not need to reference any external data sources. It is convenient and a time saver, and also something quite nice to show a customer across the counter if they are resistant to your measuring and weighing and math, either to show them that an item is real or to show them that they brought a fake into the store.

The one area where there is still a limitation is what will fit under the small sensor while still in the packaging. 1 ounce items can go under the large sensor which has lots of clearance, but fractional gold/silver needs to go under the small sensor, which has about 4 mm of clearance. Perth and Pamp bars are the most widely faked at this time, and it seems that all of the genuine bars 20 grams and under will fit under the small sensor in the packaging except the Perth 20 gram bar which is extra thick. I found that the 1/2 oz, 20 gram, and some 10 gram fake bars do not fit under the small sensor in the packaging. So basically, if a fractional gold bar in the card does not fit under the small sensor in the packaging, and it's not a 20 gram Perth bar, there's a good chance it's fake anyway, so cut it out of the card and test the bare bar. It would also be safest to crack that 20 gram Perth bar out of the card to test it.

You can check 1 ounce and some larger items in slabs under the large sensor. You'll get the resistivity values and a thickness measurement. However you typically can't see the edge of the item to confirm the diameter, so there's a limit to how thoroughly you can test slabbed items. Slabs do not fit under the small sensor. I did try to check a slabbed 1/4 gold eagle with the Refiner's Wand, however I did not get a reading. The coin was too small, and I'm not sure that the Refiner's Wand is meant for reading through a slab anyway. I'd be curious to try it with a 1/2 oz slabbed coin but I don't have any. The Refiner's Wand is really intended for larger bars, and the Microwand for little gram bars/rounds.

If I did not have any PMV device and I was in the market for one, I would probably save up the extra cash to get the PRO over the original. If I already had an original PMV and I was using it to buy from the public, I would seriously consider upgrading to the PRO.

I'll post the video here as soon as it uploads. After reading this and watching the video, if have any other questions, feel free to post them here.

I am planning to do a pre-order offer here, I will create a separate thread for that a little later.

If you don't include the density (weight, measurements) in this, even for deep measurement the resistivity measurement alone can (or could) be spoofed for some metals.

High purity (.9999 or higher) silver is the safest, because silver having the lowest resistivity of all it's very difficult (I would argue not possible) to spoof it (maybe in the future, if someone starts loading in carbon nano-tubes) and get something that has a sub 1.60 reading. That alone is a good reason to like Canadian Maples.

But basic three 9 (.999) silver can start to be a bit difficult to segregate from copper, especially silver plated copper.

And since commercially pure gold .999 or .9999 is usually alloyed with trace silver or copper, the resistivity of those coins is usually less than the gold handbook value, and the result ends up being uncomfortably close (for me) to that of basic US coinage CuNi and would be hard to separate from that, if you're looking just at the electrical reading alone.

Well done video!

Very informative video! nicely done

Will these be any good for scrap gold/jewelry?

natsb88 wrote:

Robarons wrote:Not sure if I saw that right but the new one is $1600? That seems like a steep jump over the original.

It's not cheap, but the PMV PRO has four times as many sensors as the original and a much more complex operating system and display. I am guessing some used original PMVs will hit the market once the PROs start shipping, might be able to snag a deal on something that way.

PMV PRO List Prices
base unit - $1395
w/ one wand - $1520
w/ both wands - $1595

They will be available for less than that. I am still working out what I could offer them for, but I want to thoroughly evaluate/review one first.

While you've done a great job negotiating a special buy, commenting on the supplier's prices there is only so much you can do given the starting MSRP. My view is that they've exceeded the price point for most private parties. I thought the original PMV was a bit of a stretch, but with your group buy it came in just low enough to capture my buy, and the addition of the measurement mode made me happy with it. This one is (IMHO) 400-500 bucks overpriced. If they want to capture a larger market, the base model needs to have a $995 MSRP (with further discounting available), and the wand additions need to be a bit more reasonably priced. If they sold 5x the units at the lower price point, the lower price point would probably pay for itself and then some. Of course can always introduce a 3rd and further improved model later and then reduce the price on this model when that one comes out.

68Camaro wrote:

natsb88 wrote:

Robarons wrote:Not sure if I saw that right but the new one is $1600? That seems like a steep jump over the original.

It's not cheap, but the PMV PRO has four times as many sensors as the original and a much more complex operating system and display. I am guessing some used original PMVs will hit the market once the PROs start shipping, might be able to snag a deal on something that way.

PMV PRO List Prices
base unit - $1395
w/ one wand - $1520
w/ both wands - $1595

They will be available for less than that. I am still working out what I could offer them for, but I want to thoroughly evaluate/review one first.

While you've done a great job negotiating a special buy, commenting on the supplier's prices there is only so much you can do given the starting MSRP. My view is that they've exceeded the price point for most private parties. I thought the original PMV was a bit of a stretch, but with your group buy it came in just low enough to capture my buy, and the addition of the measurement mode made me happy with it. This one is (IMHO) 400-500 bucks overpriced. If they want to capture a larger market, the base model needs to have a $995 MSRP (with further discounting available), and the wand additions need to be a bit more reasonably priced. If they sold 5x the units at the lower price point, the lower price point would probably pay for itself and then some. Of course can always introduce a 3rd and further improved model later and then reduce the price on this model when that one comes out.

+1 Its hard to justify if a person isn't buying bullion material, that is questionable or needs to be tested, on a regular basis.

Natchez14 wrote:

Robarons wrote:Not sure if I saw that right but the new one is $1600? That seems like a steep jump over the original.

Agreed. I was hoping the price of these machines would go down over time (like practically all electronics).

+1

I might add that it is a bit frustrating owning one of the earlier generation units and then hearing about reasons why it would yield false results. It would be nice if the company had a program whereby you could send your old unit back in exchange for a really good deal on the new one.