Signs of division in firm lead to insolvency (6)
I believe the answer is:
solidi
'signs of division' is the definition.
'solidi' can be an answer for 'signs' (solidus is a kind of sign). I am not certain of the 'of division' bit.
'firm lead to insolvency' is the wordplay.
'firm' becomes 'solid' (synonyms).
'lead to' indicates taking the first letters.
The first letter of 'insolvency' is 'i'.
'solid'+'i'='SOLIDI'
'in' is the link.
Can you help me to learn more?
(Other definitions for solidi that I've seen before include "Oblique strokes" , "Slashes" , "old gold coins" .)