Michtam

writing; i.e., a poem or song found in the titles of Ps. 16;
56-60. Some translate the word "golden", i.e., precious. It is
rendered in the LXX. by a word meaning "tablet inscription" or a
"stelograph." The root of the word means to stamp or grave, and
hence it is regarded as denoting a composition so precious as to
be worthy to be engraven on a durable tablet for preservation;
or, as others render, "a psalm precious as stamped gold," from
the word "kethem", "fine or stamped gold."