Holey rocks for necklace pendants, 10 rocks 2 inches and under, hag stone necklace pendants, or use for your aquarium. Holey rock, 10 Rocks, approximately 2 inches and under. Beach rock with holes, holy rocks, beautiful holy beach rock, ocean holey rock, holey rock for your aquarium. These are one of a kind beautiful holy beach rocks that are truly stunning. No two rocks are the same. Looks great in a terrarium or fish tank, or any other project you might have in mind. These rocks have fantastic weathered holes and crevices. These come directly from the ocean so please wash if you are planning on using them in your fish tank.