What are seams and why are they needed?

Seams are the joints where two pieces of stone meet.  Seams are one of the few disadvantages of stone countertops compared to manmade materials.  We do everything possible to avoid or reduce the number of seams in a job. Then, we do everything possible to make the seams less visible.  We use an epoxy resin to secure and seal the seam.  We color the resin to make it blend with the stone.  We also try to match the color and grain of adjoining sections of stone to de-emphasize the seams.