Hi ladies and gents, I was wondering something- I have a client who has come in for me to do her nails. She is an older lady who has yellowing nails and in particular the thumb nails are very thick and yellow. She also smokes. I have read that older peoples nails can become coarse and thicker with age, is this true (and yellow). Therefore I cannot determine whether she has a contagious nail fungus or she has just aged nails?? HELP :|