I came across this 2021 $10 Solomon Islands "300" Spartan Helmet coin this week on Instagram. What a cool coin! 300g of silver and only 300 minted. In case you were wondering, no, this is not my coin. It's a little out of my budget, which is like $20 to $35 a month. LOL. But when I saw this and its dimensions (over 4" long), a question popped into mind right away. Let's say someone sends it in to be graded. Because of its odd shape, size, and depth, surely the TPG needs to have a custom holder. Since the population is so low, who pays for the custom holder? Does the TPG pass on the design and manufacturing costs to the submitter? Just curious.
Yes, NGC has oversized holders that can accommodate large-size coins. They have standard large-size holders that fit the 5 oz ATB silver rounds, but this one might need something thicker because of its relief. It's a $20 extra fee for the oversize holder. I think their very largest holders will even fit the absurd 1-kilo coins some countries decide to make. If it will fit those, it will fit this. The only potential drawback is most holders are designed for roundish things... and this is not round at all.
My thoughts also. I did see their large holders but noticed they were housing traditional round coins. I wonder how thick (deep) this high-relief helmet coin is... Surely a CT member here must have it! LOL.
As posted above in the link, There are two sizes of the NGC Oversize Holder: The medium NGC Oversize Holder (MSCH) can accommodate coins and medals up to 101.5 mm in diameter and up to 25 mm in thickness. The large NGC Oversize Holder (OSCH) can accommodate coins and medals up to 120 mm in diameter and up to 15 mm in thickness. That Spartan beauty is 110 X 63.5 mm - it wouldn't fit in the NGC oversized holders either - too thick! Neato! I have a Cook Islands silver coin with a meteorite chip in it that is shaped like the crater in the Moroccan desert where it crashed, that is in a double thick PCGS holder. Found the pics:
NGC has a Mega Holder that can hold items up to 28mm in thickness. Did you miss scrolling down to it?
NGC Mega Holder® The world’s largest coins also benefit from the protection of the NGC holder. Coins as large as 180mm in diameter and 28 mm in thickness can be encapsulated in the NGC Mega Holder. Contact Customer Service to confirm eligibility.
??? The Spartan is 63.5mm in thickness, the NGC Mega Holder only accommodates 28 mm max. I fear you may have missed that.
Let's say it can accommodate the thickness. But then how does it "grab on" to the sides of this odd shaped coin?
You are misinterpreting those dimensions. The Spartan is 110mm (tall) x 63.5mm (wide). There is no coin or medal that is 63.5mm thick. Here is what 63.5mm looks like. I have four medals this size that are in NGC Oversized holders.