Swanson has many forms of mineral supplements to answer just about any need. But when you began asking for this specific combination of calcium and magnesium aspartate, we realized we better get to work. Now, we're pleased to answer your call with the precise formulation most commonly requested. If your doctor or healthcare provider has recommended the aspartate form of these minerals, Swanson Premium Calcium/Magnesium Aspartate Complex is sure to fit the bill. Calcium and magnesium in aspartate form are bioavailable because aspartate acts as a mineral transporter, supporting the absorption potential to make the most of the elemental minerals provided.