Choice (Proverbs 8:10, Proverbs 8:19); tested, purified by fire; πεπυρωμένος, Septuagint. Is little worth; mere dross, in contradistinction to choice silver. So the tongue is contrasted with the heart, out of whose abundance it speaketh (Ec Proverbs 21:26, "The heart of fools is in their mouth; but the mouth of the wise is in their heart").
Septuagint, "The heart of the godless shall fail ( ἐκλείψει)."