Adcal ® contains calcium carbonate g (calcium 600 mg or Ca 2 + 15 mmol); Calcichew ® contains calcium carbonate g (calcium 500 mg or Ca 2 + mmol);Calcichew Forte ® contains calcium carbonate g (calcium 1 g or Ca 2 + 25 mmol);Cacit ® contains calcium carbonate g, providing calcium citrate when dispersed in water (calcium 500 mg or Ca .