How many letters does the top answer for “this element, when overcome with extreme heat and pressure, creates diamonds.” have?

The most common answer is carbon (6 letters).

Crossword clue: this element, when overcome with extreme heat and pressure, creates diamonds.

1 answer found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

carbon 6 letters otdb

an abundant nonmetallic tetravalent element occurring in three allotropic forms: amorphous carbon and graphite and diamo