Skeletal mineralization is initiated in matrix vesicles (MVs). the small extracellular vesicles derived from osteoblasts and chondrocytes. Calcium and inorganic phosphate (Pi) taken up by MVs form hydroxyapatite crystals. which propagate on collagen fibrils to mineralize the extracellular matrix. https://allfixelectricales.shop/product-category/dryer-drum-belt/