| http://www.w3.org/ns/prov#value | - An abundance ratio among aluminum, silicon, calcium, sulfur, magnesium, and titanium is not particularly limited, and for example, when the total quantity of the above elements is defined as 100, it is preferred that aluminum be 1 to 60%, silicon be 20 to 90%, calcium be 1 to 30%, sulfur be 1 to 20%, magnesium be 0 to 20%, and titanium be 0 to 20%, it is more preferred that aluminum be 1 to 50%, s
|
