Born in St.Louis, Missouri. Married to Marilyn. Harvard University (B.S., 1949) Harvard Graduate School of Business Administration (MBA, 1951).

R. Tettenhorst was a St. Louis collector best known for his half cent collection (the “Missouri Cabinet Collection”) sold by Goldberg’s in 2014. Tett was related to Eric P. Newman by marriage and both of their collecting careers followed similar arcs, being mentored as children by Burdette G. Johnson, a St. Louis dealer. After establishing professional careers, both built world-class collections. Tet worked his entire career at Edison Brothers Stores, a retail firm founded in 1922 by his father Irving and uncles Sam, Mark, Harry, and Simon. He began at Edison Brothers in 1953 after completing military service and rose to the rank for President in 1968, where he served until retiring in 1987. Edison Brothers was the largest retailer of women’s shoes in the United States, reaching $1 billion in sales in 1983.

Tett originally began by collecting large cents and, feeling he could not compete with top collectors in that field, began pursuing half cents. The Missouri Cabinet, containing pieces from Tet and the Eric P. Newman Numismatic Education Society , was the only collection containing every variety of circulation and proof strikes in the United States half cent series. The 2014 sale realized over $18 million, including a 1794 Cohen-7 half cent graded PCGS MS67 RB, which sold at $1.15 million. Many of the pieces came from other important half cent collections, including those of Philip M. Showers and Roger S. Cohen.

(See Bernard Alan Edison)

He used the name of his secretary, Rose Tettenhorst, to conduct his numismatic business.