"Tourmaline group". mindat.org. Diarkibkan daripada yang asal pada 2005-12-28. Dicapai pada September 12, 2005.. This website details specifically and clearly how the complicated chemical formula is structured.
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"Tourmaline group". mindat.org. Diarkibkan daripada yang asal pada 2005-12-28. Dicapai pada September 12, 2005.. This website details specifically and clearly how the complicated chemical formula is structured.