This bowl is approx 10 inches wide & 5 1/2 inches tall. There are no markings on bottom. I have seen others with the rim pattern called 'picket fence' but haven't found one with the bottom part of bowl pattern as mine. Is it yellow ware and anyway to identify age by the pattern period? If it

is picket fence on rim, what is bottom. Also, I have been told that the bottom part of the rim was used for sharpening knives, it feels rough enough but I wouldn't try it. Again, thanks in advance.