I recently had an lumber spine x-ray if i've got kidney stones will they show on this x-ray?

Kidney Stones : A plain x-ray will only see kidney stones that have partially calcified; not all kidney stones, however, have calcium in them, so if you have typical symptoms - excruciating pain radiating into the groin, for example - you may well have a stone that is not calcified. Other tests can determine if you do. Follow up with your urologist.

Sometimes: Not all renal stones are visible on a plain radiograph. Ct is much more reliable in confirming or excluding stones, and precisely indicating their position within the urinary tract.