After a short stint as a salesman in the New York store of Bulgari, he returned to Paris in 1977 and began designing pieces there from affordable materials, such as coral, moonstone and minute colored diamond.
Quick success led the self-taught Rosenthal to open a non-descript salon at 7 Place Vendôme, where he still hosts his loyal clients.
What Rosenthal has been doing since 1977 is setting gems in pavé arrangements[5] as fine as needlepoint stitches, frequently amplifying the stones' colors by mounting them in a blackened alloy.
[6] In 1994, JAR made a Parrot Tulip bangle of gold, with diamond and garnet accents, that sold at auction in 2014 for 3.25 million Swiss francs.
[9][10] In 2017, Rosenthal created his first piece of Judaica for the exhibition Menorah: Worship, History, Legend, co-sponsored by the Vatican and the Jewish Museum of Rome.