It's a wonder to me how these gold coins ever get to Choice and Gem MS grades with gold being as soft as it is.
$1 and $3 gold pieces are small and light combined with their 10% copper alloy for hardening allowed many of then to escape heavy contact and circulation marks.
What amazes me is how beat up many choice mint state $10 and $20 pieces are and still achieve MS63 level in the grading room. It seems their size, weight and relative softness account for liberal grade assignments.
As you noted this particular example saw very little circulation. Those at gem level were likely pulled from circulation and saved from the get-go. Thanks for sharing.