Pretty pattern on a nice sized agate slab.  Looks like tiny clusters of stars swirling in a cloud in the center of the slice. There are both opaque and translucent  areas in this one slice. 

Size is about 130 x 100 x 7mm thick.  Photographed wet to show details and dry to show the slab dimensions (second photo).  The dry photo is on a 10mm or 1cm to the square scale. The third photo shows the slab held up against the sun to show off the beautiful translucent areas.