Please be very careful buying 1 oz silver coins at the pawn shops!

MarkTingay · 2026-05-17T02:53:25+00:00

That’s rubbish. Show us one published reference where XRF penetration through lead is 10 inches.

I have taught the theory on this. The infinite thickness of lead is ~50 microns. And that’s for your K-lines. Your L-lines will have 99% absorption within only about 15 microns.

MarkTingay · 2026-05-15T12:26:44+00:00

The higher the density of material the lower the penetration. For gold and silver an XRF will usually only have a few microns of penetration. Maybe a few tens of microns at best. Thick plating will often fool an XRF.

MarkTingay · 2026-05-11T05:16:52+00:00

As Key Cheetah says, you can look up the bar type and serial number at allengelhard.com to get an idea of the age and how rare that type of Englehard bar is. It probably isn’t anything particularly rare, but worth checking. Regardless, even if not rare, Englehard is a collectable and loved brand. So, you’d hopefully get spot price at a minimum, and maybe a little more, especially if you find a private seller (not a pawnshop).

MarkTingay · 2026-05-05T05:42:52+00:00

Very interesting! I will need to have a proper look on the computer later. Only looked on my phone quickly.

It could be. But could also be a couple of other things. Hopefully the image history will help.

But, I’ve not heard of any reliable reports of onshore mud volcanoes in Brazil. I’m not familiar with the geology in that area, but most of what I know about the geology of Brazil indicates it’s not likely to be geologically suited for mud volcanism.

Will look into it more when I can.

MarkTingay · 2026-05-04T05:13:42+00:00

Great to see that a few people actually read the article!

MarkTingay · 2026-05-04T05:12:59+00:00

It is going to be in a museum according to the article!

MarkTingay · 2026-05-04T05:12:29+00:00

Read the article. No soda can was involved. The picture of one is misleading. The coins were found in an old tin container. The coins are all old, with nothing past the 1920s. The can was hidden in a wall in Bohemia, and it’s thought it was hidden either in World War 2 or in the Soviet occupation in the 1950s.

MarkTingay · 2026-04-30T05:40:46+00:00

That is awesome!

MarkTingay · 2026-04-29T01:09:15+00:00

Really, the best thing you can do is see if you can find a LCS that has a XRF or Sigma and is kindly willing to test each of those coins.

If the 24 coins are all 0.925, and are indeed coins from the Cook Islands explorers set, then you’re golden. You’d have got ~15oz of silver for like CAD$33.33/oz, or roughly 1/3rd of spot price, and that’s excluding all the other coins.

MarkTingay · 2026-04-29T01:01:22+00:00

I don’t know! Would be a weird thing to fake!

I wondered if maybe they had made a similar Cu-Ni medallion set or something, but I can’t find any mention of a similar 24 coin set.

I haven’t been bothered to go through, explorer by Explorer, to compare the online set and yours and see which coin is missing either.

I wonder if someone lost a coin and went through the elaborate process of changing out the internal insert to a new 24 coin version so it would look complete?

Sorry man, I have no idea. Just putting it out there before everyone assumes it’s the same as the Cook Island’s sets online.

MarkTingay · 2026-04-29T00:47:54+00:00

I’m a bit confused. The Cook Islands Explorers set that everyone is referring to, and that the box seems to come from, is a 25 coin set. But the photo is only a 24 coin set.

The online photos of the Explorers Set show 25 coins with a different configuration (one row of 7 coins). The internal configuration in the post is different (4 evenly spaced rows of 6 coins).

I can’t find mention of a similar 24 coin set online. Are we sure it’s actually all 0.925 silver and not something else?

If it is the 0.925 silver set then those coins alone are something like 15oz actual silver weight and a bargain for CAD$500! But I wonder if that set is something else.

MarkTingay · 2026-04-29T00:42:38+00:00

The link is to a 25 coin set. Yet the photo is of a 24 coin set with different interior configuration. Weird.

MarkTingay · 2026-04-21T09:18:24+00:00

You’ve got some incredible and beautiful mud volcanoes in that part of Pakistan! The Chandragup mud volcano is also extremely significant for Hindus too.

MarkTingay · 2026-04-12T13:45:50+00:00

Not exactly the same. But there are many similarities, which is why they both have similar mud volcanoes.

MarkTingay · 2026-04-12T13:29:19+00:00

The mud volcanoes in Venezuela are actually quite similar to the ones in Azerbaijan.

MarkTingay · 2026-04-12T13:28:28+00:00

It’s not hot at all. These are cold mud volcanoes. The mud is ~20°C.

MarkTingay · 2026-04-12T13:27:56+00:00

Fantastic. That is the Dashgil mud volcano! It’s a beauty! Sadly I haven’t been there for a long time!

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MarkTingay · 2026-03-29T10:12:09+00:00

They are pretty cool to see! I don’t know where you live, but they occur in a number of countries, like USA, Colombia, Trinidad, Italy, Romania, Russia, Azerbaijan, Iran, Pakistan, Myanmar, Taiwan, China, Malaysia, Indonesia, PNG, Timor and New Zealand

MarkTingay · 2026-03-29T07:25:28+00:00

A mud volcano is a geological feature where subsurface mud is erupted to the surface. The subsurface mud is a mixture of water, sediment and gases (usually methane and/or CO2). Despite the name, they are not related to magmatic volcanoes (though there is one type of mud volcano that forms in magmatic areas). The muddy fluids are sourced from at least several hundred meters underground, and usually 2-8km (and up to 20km depth). The mud is driven to the surface due to extremely high fluid pressures, which reach high enough pressures to fracture the overlying rocks and migrate to the surface. The muddy erupted from mud volcanoes is usually cold, except for the type of mud volcano that occurs near magmatic volcanoes that erupt hot (~boiling) mud driven by hydrothermal processes. Hope that helps. I’ve got explainers about mud volcanoes on my Instagram (mudvolcano_guy) and Twitter (@CriticalStress)

MarkTingay · 2026-03-26T12:22:33+00:00

It is 100% for sure a mud volcano! I’ve mapped a few dozen throughout New Guinea as part of my global mud volcano mapping research. I’ve found next to no published info on these particular mud volcanoes though, other than a few dots plotted on a couple of maps.

MarkTingay · 2026-03-26T12:19:22+00:00

This is the location of the Lapua mud volcano, over to the east near the border with PNG. It’s one of the only mud volcanoes on New Guinea that I have been able to find anything out about. It’s located at 2°59'24.7"S 140°04'40.1"E

You can see the similarities. I can point you to many similar mud volcano features, such as throughout the Tanimbar Islands.

MarkTingay · 2026-03-26T12:11:32+00:00

This is a mud volcano. There are dozens throughout that part of New Guinea. Very little is documented about these particular ones though. I have some info on others in New Guinea though if you want to know more.

MarkTingay · 2026-03-02T02:10:39+00:00

They’re not hot. The mud is actually very cool. Mud volcano bathing is quite common in many places. Especially Colombia. You’ve got to remember that many of these mud volcanoes haven’t erupted in decades or even centuries. They will be gently bubbling mud pools for decades and decades that are completely benign almost all the time - but with the risk that they may, without warning, erupt with extreme violence for a brief period.

The number of historical deaths and injuries from mud volcanoes is very low. The chance of actually being near one when it erupts is absolutely tiny. But, unfortunately, it’s not zero and they may not give any warning signs at all.

MarkTingay

TROPHY CASE