Other greens such as turnip, mustard, collard, and kale have much more calcium than oxalic acid and provide more calcium to the body. Dolomite is calcium and magnesium. Calcium is a soft, silvery white metallic element found as chalk, limestone and marble. Ca of kale which contains no oxalic acid is nearly as well assimilated as milk. In plants calcium varies in its amount in the tissues.
Calcium reduces the toxic effects of other salts in the water.
A Lack of calcium reduces meristem activity or the activity of the cell wall. It is considered immobile, so calcium in older leaves cannot be removed to younger leaves. That means a deficiency will show up in the youngest areas of the plant. Young leaf margins curl back with brown spots. Tomatoes show blossom end rot, which is the end of the tomato rots before the fruit ripens.