Hackmanite is a sodalite family mineral. It contains sulfur in addition to chlorine… It’s occurance is associated with silica undersaturated igneous rocks. Coyoto peak in Humbolt county is a diatreme of ultrabasic low silica rock which contains sodalite. I would not expect it to be found in association with nephrite or jadeite which is found in the same area in an obducted ophiolite associated with a low temperature high pressure metamorphic regime. There is an occurance of lapis lazuli which is a mixed sodalite family rock in San Bernadino county… The only other area in California that I can think of that has low silica rock is in the Mohave Desert… Mountain Pass mine is a carbonitite, the area was explored for more rare earth minerals and a low grade source was found in a swarm of shonkinite dikes south of Mountain Pass. Sodalite minerals could potentially be found in association with these alkaline igneous rocks. The geology of California is very complex but is not known for much alkaline igneous rock intrusions where sodalite is most often found.
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