"black iron" meaning in English

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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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      "examples": [
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          "ref": "2017, Ken Heathcote, We're Going To Live Forever: The Secrets To Eternal Youth, page 44",
          "text": "The problem we had was not the concept or the product, but what to do with the space. To put a beauty salon alongside a black iron gym was ludicrous.",
          "type": "quotation"
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        {
          "ref": "2021, Jane Brooke, Vegas Savages",
          "text": "There always lifting big, black iron and such, grunting, screaming out shit and slamming down the barbells […]",
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      "glosses": [
        "Weights as opposed to exercise machines."
      ],
      "id": "en-black_iron-en-noun-VOv-RuH4",
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          "Weights",
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          "exercise machine",
          "exercise machine"
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        "uncountable"
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  "word": "black iron"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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          "ref": "2017, Ken Heathcote, We're Going To Live Forever: The Secrets To Eternal Youth, page 44",
          "text": "The problem we had was not the concept or the product, but what to do with the space. To put a beauty salon alongside a black iron gym was ludicrous.",
          "type": "quotation"
        },
        {
          "ref": "2021, Jane Brooke, Vegas Savages",
          "text": "There always lifting big, black iron and such, grunting, screaming out shit and slamming down the barbells […]",
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        "Weights as opposed to exercise machines."
      ],
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          "exercise machine",
          "exercise machine"
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  "word": "black iron"
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