After the birth of our son my husband bought me a beautiful sapphire and diamond eternity ring. It was quite unusual as the stones were square. Unfortunately one of the sapphires fell out, but we luckily found it and instead of taking the ring to the jewellers to be mended, dear husband decided to do it himself.
Once fixed in place, husband handed ring to me saying 'that'll not fall out again' referring to the sapphire. How very true!
Unfortunately the glob of glue holding the sapphire in place was not transparent, the light couldn't shine through it, and it was very visible at the back of the ring which was never worn again. Still have it and wear now and again around the house- was bought a beautiful diamonds only one many years later-of which I'm very careful to ensure that it, glue and husband together are never in close proximity!