For the The Hawaiian Mint (THM)/Royal Hawaiian Mint (RHM) collectors: I recommended that you understanding the cross referencing technique between the Medcalf & Russell book and the Royal Hawaiian Mint database. It will aid you making a decision in making the purchase of a THM or RHM issue.
As an example, there is a 2MB-147 (in 18K gold) listed today at a relatively large auction site. Lets investigate this specimen identified as 2MB-147.
1) Look on page 135 of M&R. yes, 2MB-147 is listed there.
2) In the RHM database go to the start of the year 1981
3) In the RHM database, find the die pair (obverse King Kalakaua and reverse 1981 Aloha Pineapple) matches.
4) Did you get 3 rows with the die pair match? (24K gold, sterling and bronze)
5) No 18K is listed for the die pair match. Something fishy is happening…
6) Search for the M&R term 2MB-147. Any hits? The fish is smelling bad…
Conclusion: No 18K is listed for the die pair (Medcalf & Russell is in error). BVN did take the time to cross reference his issues with the M&R book. 2MB-147 simply does not exist (in 18K gold). There is a single 24 K gold listed in the RHM database (maybe…maybe not..). I would do a one-on-one inspection of the coin to determine is its gold plated or 24K gold.
I have a suspicion that the 2MB-147 listed is a gold plated bronze. Someone simply used M&R book to add the identifier 2M-147 on the holder. I recommend you ignore the label and inspect the coin carefully.
If you go back to the RHM database and look at the other obverse designs with the Aloha 1981 Pineapple reverse. The Kamehameha I match is labeled gold plated. As well as the Madame Pele match. The Captain Cook is not labeled gold plated as well as the Kalakaua obverse. It can be said that the RHM database is in error for not listing these two (Captain Cook and Kalakaua) as gold plated. I did update my personal copy of the RHM database with this error. As for the auction listing, no thank you…I’ll pass on it….
By the way here is a bronze1981 pineapple that is not gold plated https://thehawaiiananumismatist.com/2013/11/02/1981-uniface-pineapple-design/ Would this coin sell as a bronze? Maybe as a gold plated bronze….