As I recall, the Tarn-X, unless it is thoroughly rubbed off after rinsing, leaves a kind of surface patina that makes the surface seem a bit like pewter. But seemed the best stuff at getting off really heavy tarnish. That patina will come off if you use the Hagerty's on it after the Tarn-X treatment.
Gary Merrill
Wessex EEb Bass tuba (DW 3XL or 2XL)
Mack Brass Compensating Euph (DE N106, Euph J, J9 euph)
Amati Oval Euph (DE 104, Euph J, J6 euph)
1924 Buescher 3-valve Eb tuba (with std US receiver), Kelly 25
Schiller American Heritage 7B clone bass trombone (DE LB K/K10/112/14 Lexan, Brass Ark MV50R)
1947 Olds "Standard" trombone (Olds #3)