Pioneer Nutrition Calcium Magnesium Supplements, Mineral, 60 Count

What the brand says

This product features exceptionally well-utilized forms of calcium (microcrystalline hydroxyapatite [much], citrate and malate), plus Vitamin D-3, boron and magnesium from three sources for enhanced bioavailability. Pioneer's pure quality much comes from the freeze-dried, whole bone of pasture-fed new Zealand or Australian cattle. Its naturally proportioned complex of inherent bone matrix proteins and key trace minerals provides added nutritive support for healthy bone density.