The Santa María and Antares Zn-Pb(-Ag) skarn deposits in the Velardeña Mining District are located in central–NW Mexico. They lie 470 m apart along the contact between Oligocene felsic intrusions and Cretaceous limestones, and were developed during prograde, retrograde, post-ore (Santa María), and late stages. Firstly, the prograde stage was formed by fluids at ~ 600 °C and 15 wt% NaCl equiv., and consists of garnet + wollastonite ± clinopyroxene and biotite ± K-feldspar assemblages. Secondly, the retrograde/ore stage was formed by fluids at 300–500 °C with salinities of 20–30 wt% CaCl₂ (Santa María) and > 40 wt% NaCl equiv. (Antares). It comprises assemblages of chlorite, amphibole, epidote, calcite, scapolite, quartz, sericite, adularia, fluorite, and muscovite associated with sphalerite, pyrite, galena, pyrrhotite, arsenopyrite, chalcopyrite, and Pb-Bi-Sb sulfosalts. Thirdly, the post-ore stage was formed by fluids at ~ 400 °C and 20–30 wt.% CaCl₂ and comprises poorly mineralized calcite veins. Fourthly, the late stage was formed by fluids at < 300 °C and 20–30 wt.% CaCl₂ (Santa María) and ~ 15 wt% NaCl equiv. (Antares), and crystallized tetrahedrite-group minerals and pyrite + marcasite. δ¹⁸O_fluid between ~ 14‰ and 23‰ at Santa María and between ~ 12‰ and 17‰ at Antares show a less-modified magmatic affinity for mineralizing fluids at Antares; δ¹³C_fluid between 0‰ and –6‰ register recycling of sedimentary C. Moreover, sulfides with δ³⁴S_VCDT between –3‰ and 2‰ reveal a magmatic source for S. Altogether, these data suggest that, at Santa María, magmatic-derived fluids actively interacted with the wall rocks, whereas at Antares the fluid-rock interaction was milder. In both deposits, metal deposition was triggered by the cooling and neutralization of ore-bearing fluids with carbonate rocks. Our ⁴⁰Ar/³⁹Ar dates for adularia of ca. 37.5 Ma place the deposits within the Eocene–early Miocene metallogenetic epoch of central–NW Mexico, during which other world-class skarn-epithermal systems were emplaced (e.g., Concepción del Oro and Mazapil-Peñasquito).

Velardeña 矿区的 Santa María 和 Antares 锌铅（-Ag）矽卡岩矿床位于墨西哥西北部中部。它们沿着渐新世长英质侵入体和白垩纪石灰岩之间的接触面分布，相距 470 m，并在顺行、逆行、矿后（圣玛丽亚）和晚期阶段发育。首先，前级由约 600 °C 和 15 wt% NaCl 当量的流体形成，由石榴石 + 硅灰石 ± 单斜辉石和黑云母 ± 钾长石组合组成。其次，逆行/矿石阶段由 300–500 °C 的流体形成，盐度为 20–30 wt% CaCl ₂ (Santa María) 和 > 40 wt% NaCl 当量。（心宿二）。它包括绿泥石、角闪石、绿帘石、方解石、方沸石、石英、绢云母、长石、萤石和白云母的组合，并伴有闪锌矿、黄铁矿、方铅矿、磁黄铁矿、毒砂、黄铜矿和铅-铋-锑硫盐。第三，矿后阶段由约 400 °C 和 20-30 wt.% CaCl ₂的流体形成，并包含矿化不良的方解石脉。第四，后期由 < 300 °C 的流体和 20–30 wt.% CaCl ₂ (Santa María) 和 ~ 15 wt% NaCl 当量形成。（Antares），以及结晶的四面铁矿族矿物和黄铁矿+白铁矿。圣玛丽亚 (Santa María) 的δ ¹⁸ O_流体在约 14‰ 至 23‰ 之间，安塔瑞斯 (Antares) 的 δ 18 O 流体在约 12‰ 至 17‰ 之间，显示出对安塔瑞斯 (Antares) 矿化流体的岩浆亲和力变化较小；δ ¹³ C_流体在 0 ‰ 和 –6 ‰ 之间记录了沉积物 C 的再循环。此外，δ ³⁴ S _VCDT在 –3 ‰ 和 2 ‰ 之间的硫化物揭示了 S 的岩浆来源。总而言之，这些数据表明，在圣玛丽亚，岩浆衍生的流体与围岩发生积极的相互作用，而心宿二的流体-岩石相互作用则较为温和。在这两个矿床中，金属沉积是由含矿流体与碳酸盐岩的冷却和中和引发的。我们的⁴⁰ Ar/ ³⁹ Ar 日期为 ca. 的 adularia。37.5Ma将矿床置于墨西哥西北部中部的始新世-早中新世成矿时代，在此期间出现了其他世界级的矽卡岩-浅成热液系统（例如Concepción del Oro和Mazapil-Peñasquito）。