The Idiom Attic - a collection of hundreds of English idioms, each one explained.
The meaning of "where theres muck theres brass"
" Where there's muck there's brass "
Meaning:
Dirt and muddle are evidence of products being manufactured and money (brass) being made.
Example:
Stuff was coming in and out of the factory yard every five minutes and debris was piled everywhere. Business was brisk though - where there's muck there's brass you know.