UBB.threads Forums General Interest Restoration, Conservation, and Maintenance Forum How old is my spider?

Hey guys,
I have a strange question;
I have a knife with a questionable etch. The etch itself is perfect and absolutely text book, the only problem is that it is a voos mark on a TR gravity knife (thread in misc. dagger forum).
Anyway, in an attempt to learn somthing about the maker mark I inspected it very closely under a 12x loop. I discovered that what I had previously thought was a flaw in the etching of the letter "G" in "solingen" is actually some corrosion and spidering (about the size of a pinhead). My question is; how long would it take for spidering to develop? I am sure it depends on environmental ciriumstances, but any guess?
Thanks in advance,
Johnny