The invention relates to acid neutralizer technology, specifically involving a pure nano calcium powder and its preparation method, the nano calcium powder purity include the weight of the raw material: 3-7 parts pearl, 8-12 parts mother of pearl, 2-3 parts red coral, 20-30 parts oyster shell, clam shell 35-55 parts, Giant Clam 5-10 parts, pangolin shell 1-3 and 1-7 parts “ore” defined as limestone, cold water stone, and goose pipe rock. The preparation methods include cleaning, primary grinding, heat decomposition, rules grinding, nano grinding and mixing. Nano calcium pure powder of the present invention relates to the specific natural raw materials, and strict control of the nano calcium powder purity can provide human body absorption rates over 99%. The preparation method of the invention process is simple, convenient operation and control, stable quality, high yield, can be large-scale industrial production.
