Here's the
Trade dollar that initiated this thread ...


In his 2003 catalog, Dr. Brunk recorded four specimens of this counterstamp, B#-453, with the latest date being 1878. Three of them were
Trade dollars: 1875, 1877 and 1878. There was one quarter, dated 1875. It's likely that more specimens have yet to be recorded. Note that Brunk does not typically record mintmarks, simply the dates.
Neither Brunk nor Rulau offered an attribution back then, being 2003-4. Dur to the unusual surname and combination of initials,
R.I. LOMAS, I believe that the issuer was one Robert I. Lomas, a NY City restauranteur. Here are my database notes ... I use cap letters for easier reading:
ROBERT I. LOMAS APPEARS IN TROW'S 1872 NY CITY DIRECTORY AT 303 GRAND AVE, SELLING DRY GOODS, ALSO, HE HAD AN EATING HOUSE AT 243 CENTRE ST. HIS PARTNER IN THE DRY GOODS BUSINESS WAS A WM. ABBOTT. HE MAINTAINED HIS RESTAURANT BETWEEN 1859-86; THIS, AS PER DIRECTORY LISTINGS. LOMAS DIED ON MAY 3, 1899, AT HIS BROOKLYN HOME. HE WAS A MASON, A MEMBER OF PUTNAM LODGE. UPON HIS DEMISE, THE TRENTON TIMES DESCRIBED HIM AS "A FAMOUS RESTAURANT MAN OF OLDER NY."