"not a nova" I have several and they all have the classic pelt defined, cutlines on each side of the mib and at each end of the two ribbons. This is one of mine, at 15/16ths, every one locks like this or very close to it in construction, though the colors do vary greatly, all have the classic pelt design, no swirling, these were a later pelt marble, a one day run, sometime in 1988 along with the so called root beer floats, they say all larger marbles but I have seen these down to 11/16ths.