# How to take intersection of 3d graphics for 3d printing

The following two-lobed blob is the union of two spheres, and it appears (?) that I can Export[] it to STL for 3d printing:

blob = Graphics3D[{Sphere[{0,0,0}, 1], Sphere[ {0,0,0.5}, 1]}]


How would I create the intersection instead of the union?

DiscretizeRegion[