I have 1 coin and would consider adding another. They are usually about 1/5th or 1/6th of an ounce so affordable. Small mintages done by other European mints on behalf of His Holiness. You can get these sub-1 ounce coins up to Gem Mint 65 for a modest premium to melt value which I think is kind of cool. I don't think many people want to hold these coins -- or maybe I'm wrong ? -- because they might not find a willing buyer (though if you pay melt or near-melt, you really don't risk much). Anybody have any of these coins ?
As it turns out my, 1931 Vatican 100 Lire G100L gold has a mintage of 3,343 and is just over 1/4 ounce (90% fineness, 8.8 grams total weight).
Years ago, when I first learned about coins from the Vatican, I wanted a set, but I never ended up buying one (I recall bidding on some on eBay but not enough). Then I moved on to other interests. As far as gold, I think it would be just like many of the common European gold coins: you can find them at a modest premium to melt and expect a discount to melt when selling (from a few percent up to 10-15% depending on the dealer).
I only have base metals and a few silvers from the Vatican, but I like the low mintages. I think this wartime brass Centesimi may have been a junk bin find. 5000 mintage.