5 Dollars - Elizabeth II Pope Francis 80th Birthday

Struck to mark Pope Francis's 80th birthday in December 2016, this miniature gold issue belongs to a category of fractional commemoratives — sometimes called "mini gold" coins — that proliferated sharply in the 2010s as mints sought collectible price points below one gram. Cook Islands, a self-governing territory in free association with New Zealand, issues coins through licensing arrangements and holds no diplomatic relationship with the Holy See.

At 0.311 grams, this is among the smallest gold coins in regular commemorative production — roughly one-hundredth of a troy ounce.