blˈæk kˈæzəm wʌz sᵻlˈɛktᵻd fɔːɹ kənsˌɪdɚɹˈeɪʃən æz ɐ nˈæʃənəl nˈætʃɚɹəl lˈændmɑːɹk ˌɛnˌɛnˈɛl ɪn nˈaɪntiːnhˈʌndɹɪd sˈɛvənti fˈaɪv ˈæftɚ nˈæʃənəl pˈɑːɹk sˈɜːvɪs pˌɜːsənˈɛl ˈɛntɚd ˌɪntʊ ðə kˈeɪv ænd sˈɔː ðə hˈɛlɪktˌaɪt kɹˈɪstəl dɪsplˈeɪ ɪnðə lˈændmɑːɹk ɹˈuːm.
Black Chasm was selected for consideration as a National Natural Landmark (NNL) in 1975 after National Park Service personnel entered into the cave and saw the helictite crystal display in the Landmark Room.