You don't even need the calcium with it!!
CHECK your supplier of raw cacao, though... the demand is growing, and many suppliers are too hasty in checking the safety of their cacao.
If you'd like, I can direct you to the suppliers that I know to thoroughly test their chocolate... where I buy mine that I trust is -safe-. A 'raw guru' I'm friends with eats Cacao for the Magnesium and health benefits.. in the past he had Chronic Fatigue and slept 16 hours a day.
Leafy greens are high suppliers of magnesium, too! A Wellness Practitioner that I know STOPPED taking his Magnesium with Calcium supplement when he began ingesting powdered Barley grass with Alfafa.. he said his health has jumped tremendously. The product is called Organic BarleyMax by 'A Hallelujah Acres' [it's raw, like cacao].
I began taking it after I saw his results.. he was a prime user of the Magnesium and Calcium supplement.
I'll open my e-mail for you, if you'd like more info!!