Just wondering if anyone (in the UK in particular) has had their cat tattoo'd? I was thinking that if the ears were not too dark it might be a quicker way to see if the cat had ID than scanning for a chip. Does it work well enough on black ears? A while ago during a check up I asked the vet to check the microchip and he couldn't find it at first as it had moved, it made me think about a back up plan. A marked ear would be easier to spot, no need to take the cat to a rescue or vet for scanning and wouldn't migrate.