Only concern about heavy metals of your tourmaline sample is relatively high level of lead (Pb) around 32 ppm (will fax to you) via ICAP. Is there any way to reduce Pb in tourmaline?
5. The data of 36.72% SiO2 you mentioned might be the total SiO2 of tourmaline. As you know, the majority of SiO2 in tourmaline is the silicate with tetrahedral structures that is not of our concern but an impurity of free crystalline silica (AKA quartz) is strictly limited for a food process in U.S. As indicated in our XRD pattern data (will fax to you), the major pattern of free silica at two theta=26.65 degree is unfortunately overlapped with lepidolite mica and dravite tourmaline peaks of your tourmaline sample. Therefore it is rather difficult to quantify the amount of free silica in your tourmaline sample via XRD. A: 1. Yes, our 2500 mesh tourmaline powder source is in Yunnan indeed. Moreover all of our tourmaline is brown TRAVITE tourmaline, which doesn¡¯t contain any SCHORL tourmaline (but it¡¯s not excluded that a little bit SCHORL tourmaline is interfused in milling process). Of cause this tourmaline powder is made by our company and 450 and 800mesh tourmaline powders are mil
5. The data of 36.72% SiO2 you mentioned might be the total SiO2 of tourmaline. As you know, the majority of SiO2 in tourmaline is the silicate with tetrahedral structures that is not of our concern but an impurity of free crystalline silica (AKA quartz) is strictly limited for a food process in U.S. As indicated in our XRD pattern data (will fax to you), the major pattern of free silica at two theta=26.65 degree is unfortunately overlapped with lepidolite mica and dravite tourmaline peaks of your tourmaline sample. Therefore it is rather difficult to quantify the amount of free silica in your tourmaline sample via XRD. A: 1. Yes, our 2500 mesh tourmaline powder source is in Yunnan indeed. Moreover all of our tourmaline is brown TRAVITE tourmaline, which doesn’t contain any SCHORL tourmaline (but it’s not excluded that a little bit SCHORL tourmaline is interfused in milling process). Of cause this tourmaline powder is made by our company and 450 and 800mesh tourmaline powders are mille
