The few metallurgical analyses that have been conducted revealed oxidized forms of the most frequent elements of common rocks: silica, manganese, and aluminum.
(The few metallurgical analyses; have been conducted; ) (The few metallurgical analyses that have been conducted; revealed; oxidized forms of the most frequent elements of common rocks)
The few metallurgical analyses The few metallurgical analyses that have been conducted
have been conducted revealed
oxidized forms of the most frequent elements of common rocks