Multistage W–mineralization and magmatic–hydrothermal fluid evolution: microtextural and geochemical footprints in scheelite from the Weondong W–skarn deposit, South Korea

•Weondong W-skarn deposit was formed by multistage mineralization processes.•Weondong W-skarn deposit is moderate to highly oxidized skarn deposit.•Zoning textures of prograde scheelite suggests periodic fluid flux of skarn system.•Retrograde pure scheelite was formed by dissolution of prograde scheelite.•Magmatic fluid forms initial scheelite, followed by meteoric water mixing during retrograde.