The description on the Stack's website refers to H. Dudley Coleman, who, among many other accomplishments, was Melter & Refiner of the New Orleans Mint from 1899 to 1905 and member of the Assay Commission in 1912. He died in 1926.

As the description mentions, the Medal shows service from 1899 to 1941 and is actually for H. Dudley Coleman, who was usually referred to as "Hubert D. Coleman" and was, I believe, the son of H. Dudley Coleman.

When H. Dudley Coleman was appointed Melter & Refiner of the New Orleans Mint, he hired Hubert D. Coleman as Weigh Clerk. Hubert D. Coleman worked in the M&R Department of the New Orleans Mint until early 1905, when President T.R. Roosevelt appointed him to be Melter & Refiner, replacing his father. (He was nominated as Hubert D. Coleman, Jr.) He served as Melter & Refiner until the New Orleans Mint was closed for coinage, when he was hired as assistant melter & refiner of the Philadelphia Mint.

There is a notation in the Mint Annual Report for the FYE June 30, 1911: "During the year Mr. Hubert D. Coleman, formerly melter and refiner of the New Orleans Mint, now closed to coinage operations, was appointed assistant melter and refiner of this institution [the Philadelphia Mint] and entered upon his duties November 4, 1910."

Unfortunately, the Official Register of Government Officers stopped listing all or most of the employees of the Mints after 1905, so I can't track his career. However, I have seen some Census reports that show Hubert D. Coleman as a resident of Philadelphia in the 1920s.

By the way, about a year or so ago, noted numismatic researcher Roger Burdette mentioned to me that these retirement medals were usually gold plated and an actual gold medal would have had to have been specifically authorized by the Secretary of the Treasury, and, therefore, a copy of the authorization should exist in the National Archives.

To read the entry in the Biographical Directory of the United States Congress for Hamilton Dudley Coleman, see: http://bioguide.congress.gov/scripts/biodisplay.pl?index=C000619

Unfortunately, I have no idea why Hubert D. Coleman was referred to as "junior", when his (presumed) father was Hamilton Dudley Coleman. The elder Coleman was nominated by President McKinley as "H. Dudley Coleman" and I haven't yet found an obituary for either Coleman to confirm the relationship.

To read the earlier E-Sylum article, see:
SELECTIONS FROM THE STACKS-BOWERS FEBRUARY 2016 RARITIES SALE : Lot 70: U.S. Mint Retirement Medal (www.coinbooks.org/esylum_v19n05a28.html)