32S)
V-CDT − 1] × 1000, where V-CDT is the Vienna-Canyon Diablo Troilite standard) in lunar samples returned by the Apollo missions (
21). These studies found that lunar mare basalts, representing a range in major element compositions, have a remarkable uniform whole-rock acid-volatile (extraction with 3 M HCl) sulfur isotope ratios with a mass-dependent mean isotopic composition of δ
34S = +0.58 ± 0.05‰ (
2). This mean value is within the range measured for carbonaceous chondrites but is heavier than that reported for the Earth’s mantle (δ
34S = −1.28 ± 0.33‰) (
22), suggesting a different δ
34S value between the Earth’s and Moon’s interiors. A full compilation of mare basalt whole-rock δ
34S values, irrespective of the analytical technique used (different acid-volatile extraction, combustion in an oxygen atmosphere, or a combination of both), has a similar average but with a larger uncertainty (δ