any uses of this element?
Steelmaking, maintenance-free automotive batteries, to strengthen aluminium alloys used for bearings, used to store hydrogen gas
Calcium
The largest use of metallic calcium is in steelmaking, due to its strong chemical affinity for oxygen and sulfur. Its oxides and sulfides, once formed, give liquid lime aluminate and sulfide inclusions in steel which float out; on treatment, these inclusions disperse throughout the steel and became small and spherical, improving castability, cleanliness and general mechanical properties. Calcium is also used in maintenance-free automotive batteries, in which the use of 0.1% calcium–lead alloys instead of the usual antimony–lead alloys leads to lower water loss and lower self-discharging. Due to the risk of expansion and cracking, aluminium is sometimes also incorporated into these alloys. These lead–calcium alloys are also used in casting, replacing lead–antimony alloys. Calcium is also used to strengthen aluminium alloys used for bearings, for the control of graphitic carbon in cast iron, and to remove bismuth impurities from lead. Calcium metal is found in some drain cleaners, where 
where does the majority of maple syrup come from Canada from which trees is this syrup made? Sugar maple (Acer saccharum), the black maple (A. nigrum), and the red maple (A. rubrum) why these trees are used to make this syrup? Because of the high sugar content (roughly two to five percent) in the xylem sap of these species. what nutritional values it provides? Water, carbohydrates (sugars), manganese, riboflavin, zinc and calcium can you tell me the physical characteristics of the last element from the above list? Melts at 842 °C, boils at 1494 °C,  density is 1.55 g/cm, Calcium is harder than lead which countries are the major producer of this element? China, Russia, United States can you mention some food products which contains this element? yogurt, cheese, sardines, salmon, soy products, kale, and fortified breakfast cereals
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Calcium [SEP] Uses
The largest use of metallic calcium is in steelmaking, due to its strong chemical affinity for oxygen and sulfur. Its oxides and sulfides, once formed, give liquid lime aluminate and sulfide inclusions in steel which float out; on treatment, these inclusions disperse throughout the steel and became small and spherical, improving castability, cleanliness and general mechanical properties. Calcium is also used in maintenance-free automotive batteries, in which the use of 0.1% calcium–lead alloys instead of the usual antimony–lead alloys leads to lower water loss and lower self-discharging. Due to the risk of expansion and cracking, aluminium is sometimes also incorporated into these alloys.