Platinum is usually found pure.
It is a compound
In nature, titanium is always found as a compound, not as a pure metal. Titanium is highly reactive (although less reactive alloys can be made from it).
Calcium is never found in its elemental form in nature.
Einsteinium is an artificial element; it is prepared as a compound, probably as an oxide or as a compound with halogens.
Technetium is found in both in a compound and pure forms
Platinum is usually found pure.
Californium is a pure element.
pure element
In pure form.
It is a compound
Usually it is found in compound form but can easily as a pure element, just depends on the conditions
In nature, titanium is always found as a compound, not as a pure metal. Titanium is highly reactive (although less reactive alloys can be made from it).
if sodium is in a compound, it will not be in natural state. natural state implies that it is a pure element. ie not a compound
It is found in nature in its pure form (not as a compound).
In the nature zirconium is found as zirconium silicate or other compounds.
Calcium is never found in its elemental form in nature.