I have no idea on the No. 1 in the logo. I suppose the original owner could've just had that engraved on there for one reason or another. Maybe he or she had two of them and wanted to be able to quickly tell which was which. Who knows.

As for the color difference, that is likely due to age. Most blue Hammers I saw started off baby blue and ended up kind of a sea green color as they aged and collected oil/dirt. I would consider getting it resurfaced and/or doing a hot water bath or two to see if it lightens up a bit.
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Bowling bad since 1979 with no end in sight

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Lots of users had their names or something engraved in the Hammer logo.  I have never seen a #1 in the Hammer logo.  I think it's been engraved.

If you look at old Hammer engravings they look much like Visionary's engravings of today which makes sense.
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Scott

Back in the day when they were on the shelf in the pro shop we had to rotate them as the exposure to sunlight would turn them green. This also used to happen on the Cobalt Rhino
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