...Naturally occurring silver (47Ag) is composed of the two stable isotopes 107Ag and 109Ag in almost equal proportions, with 107Ag being slightly more abundant (51.839% natural abundance). Notably, silver is the only element with multiple NMR-active isotopes all having spin 1/2. Thus both 107Ag and 109Ag nuclei produce narrow lines in nuclear magnetic resonance spectra.[4] - ' the only element with 1/2 spin isotopes '
...ur exactly correct - frequency - why do all great musical bands tune to 432hz - why was the standard changed to 440hz