I found this rock in a glacial till in north central Washington State, on the east side of the Cascade Range. The dark round crystals are roughly 1 inch (2.54 cm) by 2 inch (5.08 cm) in size. The center of the lowest point of erosion zone is mid slope but not near the other larger heavier boulders that stopped at the toe of slope change. The rock itself is nearly three feet long (91 cm) and fourteen inch diameter (35.56 cm) and only two of these exist on strata surface. This was likely uncovered from recent post wildfire flooding. The rock attracts a magnet from nearly two feet (61 cm) away.
It's not possible to tell what it is from this photograph, but from the limited information given, my first guess is a coarse grained gabbro with large phenocrysts of pyroxene.
There are only a few places in the world where one finds "orbicular granites" like in this australian web photo:
What you may have found is it's mafic equivalent: an ophitic basalt (or gabbro) in which large pyroxenes enclose feldspar cores. They're common enough in mafic igneous bodies, but yours are seriously on steroids!
Of course, without seeing any detail, your rock could be sedimentary in origin....in which case it could be just a weird magneto-conglomeratic pile of dinosaur doo-doo :)