local real    mineX

    local real    mineY

    local integer mineGold

    local unit    newMine

    // Make sure we're replacing a Gold Mine and not some other type of unit.

    if GetUnitTypeId(goldMine) != 'ngol' then

        return null

    endif

    // Save the Gold Mine's properties and remove it.

    set mineX    = GetUnitX(goldMine)

    set mineY    = GetUnitY(goldMine)

    set mineGold = GetResourceAmount(goldMine)

    call RemoveUnit(goldMine)

    // Create a Haunted Gold Mine to replace the Gold Mine.

    set newMine = CreateBlightedGoldmine(whichPlayer, mineX, mineY, bj_UNIT_FACING)

    call SetResourceAmount(newMine, mineGold)

    return newMine

endfunction