daij

removed first sense because this is a proverb, not a noun 
referring to the figurative bream.

@@ -12 +12,2 @@
-<gloss>something that is not what it once was but it is still high class</gloss>
+<misc>&proverb;</misc>
+<gloss>a diamond on a dunghill is still a diamond</gloss>

ルミナス, 中辞典 (extra gloss).

Bear in mind it's a proverb. I don't think a language learner should be worrying too much about the literal meaning of the Japanese, much less agonizing over any ellipsis. We have plenty of expressions where we also give a "lit" Japanese version, and I'd hate to see the English mangled just to make it more 直訳.

@@ -13,0 +14 @@
+<gloss>an old eagle is better than a young crow</gloss>

See below.

I have not changed the above. My thoughts were triggered by the fact that in some text the above expression is followed by "です" or "だ"; plus also sometimes an exphasis, etc., e.g., "な".

What I was thinking is this: that the parts in the meanings above which turn the expression into a complete statement should be included in brackets, e.g., [lit] even if (it's) rotten, (it's still) sea bream. I am stating this because when the meaning is preceded by the concept of "the literal meaning", namely; upholding the exact or primary meaning of a word or words, the inclusion of "it's" and "it's still" seems to be incorrect. I don't wish to become the pedant, but I am thinking that the novice may be deviated from the true concept of such an expression when trying to balance literal meaning of the Japanes head-word with the meaning given following the prefix [lit].

I think that I would like to see such an entry for the meaning of such expressions set out something like this:

"[this expression is idiomatically usually used simply as 'くさってもたい' and conveys the meaning of] something that is not what it once was but it is still high class; quality is quality; [lit] even if (it's) rotten, (it's still) sea bream.

@@ -14,1 +14,1 @@
-<gloss>even if it's rotten, it's still sea bream</gloss>
+<gloss g_type="lit">even if it's rotten, it's still sea bream</gloss>