How can I set it up so that I only have one starting product per mine?
So either stone or metal or sulfur or high-grade metal?
I can't get any further, my config is attached.

Hopefully you can help me. :)

{
  "Settings": {
    "Use Teams": true,
    "Use Friends": true,
    "Use Clans": true,
    "Block damage another player's survey crater": true,
    "Block deploy a quarry on another player's survey crater": false
  },
  "Chat Settings": {
    "Chat Prefix": "<color=#00FFFF>[BackPumpJack]: </color>: ",
    "Chat SteamID Icon": 0
  },
  "Permission List": [
    {
      "Permission": "backpumpjack.use",
      "Priority": 0,
      "Oil Crater Chance": 20.0,
      "Oil Crater Settings": {
        "Minimum pM": 5.0,
        "Maximum pM": 10.0
      },
      "Normal Crater Settings": {
        "Modify Chance (If not modified, use default mineral)": 50.0,
        "Minimum Mineral Amount": 1,
        "Maximum Mineral Amount": 1,
        "Allow Duplication Of Mineral Item": false,
        "Mineral Items": [
          {
            "Mineral Item Short Name": "stones",
            "Chance": 20.0,
            "Minimum pM": 120.0,
            "Maximum pM": 180.0
          },
          {
            "Mineral Item Short Name": "metal.ore",
            "Chance": 20.0,
            "Minimum pM": 15.0,
            "Maximum pM": 30.0
          },
          {
            "Mineral Item Short Name": "sulfur.ore",
            "Chance": 20.0,
            "Minimum pM": 15.0,
            "Maximum pM": 30.0
          },
          {
            "Mineral Item Short Name": "hq.metal.ore",
            "Chance": 20.0,
            "Minimum pM": 1.5,
            "Maximum pM": 5.0
          }
        ]
      }
    },
    {
      "Permission": "backpumpjack.vip",
      "Priority": 1,
      "Oil Crater Chance": 20.0,
      "Oil Crater Settings": {
        "Minimum pM": 2.5,
        "Maximum pM": 5.0
      },
      "Normal Crater Settings": {
        "Modify Chance (If not modified, use default mineral)": 50.0,
        "Minimum Mineral Amount": 1,
        "Maximum Mineral Amount": 1,
        "Allow Duplication Of Mineral Item": false,
        "Mineral Items": [
          {
            "Mineral Item Short Name": "stones",
            "Chance": 20.0,
            "Minimum pM": 120.0,
            "Maximum pM": 180.0
          },
          {
            "Mineral Item Short Name": "metal.ore",
            "Chance": 20.0,
            "Minimum pM": 15.0,
            "Maximum pM": 30.0
          },
          {
            "Mineral Item Short Name": "sulfur.ore",
            "Chance": 20.0,
            "Minimum pM": 15.0,
            "Maximum pM": 30.0
          },
          {
            "Mineral Item Short Name": "hq.metal.ore",
            "Chance": 20.0,
            "Minimum pM": 1.5,
            "Maximum pM": 5.0
          }
        ]
      }
    }
  ],
  "Version": {
    "Major": 1,
    "Minor": 4,
    "Patch": 11
  }
}​