I’ve did some research and found what the acronym HPM stands for…(not revealing it at this time)

NumisMaster (and its source) has the acronym wrong…

M&R has the acronym wrong….

For now, I can say it’s a mint that was physically located in Hawaii…

So far two items have been identified in 1991 M&R (makes these items pre-1991) …

Found a third item that is not listed in M & R … still researching this item…

It is my understanding that items from this mint are extremely hard to locate…..

To be continued …