Removing a coin from a lucite/acrylic paperweight block.

Unless coins were really valuable, I wouldn't touch it. Freeing the coins will take a lot of work and solvent plus a band saw or table-mounted jig saw. Mike

 

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I wonder what happens if you soak it in liquid nitrogen and then smash it with a hammer?

 

I tried putting a chunk in the freezer and then hitting it with a hammer. It did shatter, and I got coins out, but several of them were bent from the stress/strain. (These were clad and polished, so no great loss.)

 

So liquid nitrogen might work, since the block would be way way colder and perhaps less force needed to shatter it.

 

Might try thermal stress cracking. Use dry ice to cool. Dry ice is usually much easier to obtain than liquid nitrogen … many grocery stores carry it. However, dry ice is not as cold as LN but is not as dangerous to handle either. Wear thick gloves and remember it continuously generates carbon dioxide gas. Once the block is completely at dry ice temperature, drop it in a pot of boiling water or, even better, cooking oil that is near boiling. Be careful not to get splattered.

Mike

 

I'm not enough of an engineer to calculate the forces and effects on a coin from this thermal-stress approach, but I'm not confident that it would be safe for the coin(s). The thermal stress on the coin shouldn't matter, but the forces from the deforming plastic might.

 

With a bandsaw you could cut away the greatest majority of the plastic, then use the acetone to individually free each coin.

 

That's more time, though. Especially when the plastic softens due to friction and jams your saw blade. Ask me how I know.

 

I believe the answer is as would be mine: As it's probably an unequaled challenge for most, but desirable for some!

I've rolls of that coin/condition, but I'd loved to secure it in my milling machine, cutting parallel to the coin body faces within .03", and within the same of the diameter edge, before putting it in my hydraulic press between 2 rubber sheets.

Lightly press, POP/FREE!

A COUPLE HOURS STRESS-RELIEF WHILE WORKING ON OTHER CHALLENGING PROJECTS!

I completed a portion of this exercise often, when relieving slabbed Gold Eagles from their "cage", for TPG re-submission!

 

Yup, the usual blades made for wood and metal are melt-city when used on plastic. However, there are special saw blades and drill bits made for plastic. I know from experience they make a huge difference. Buying them for a one-off, inexpensive project ... probably not worth it. Mike

 

Try microwaving it! LOL

Put a shrimp on the barbie!

 

I went to take a look and it was gone.
Someone bought it for what it was... probably at today's $17.50 price tag.

 

Yep, sometimes you get beaten to the punch. This probably isn't one to loose too much sleep over, though.

 

No sleep loss at all.
I ended up picking up a sterling silver Taxco pendant for $0.50
An interesting box of rocks for $20 with one rock looking like it has a little bit of gold in quartz.
A large black mixing tub for $2.50 and a tile/rock saw on a cart for $75.

 

good job