These black umbonium shells are great for all your shell craft projects. They range in size from approximately 3/8" to 5/8". You will receive one 3" x 4" bag full, that's about 1/2 cup, hundreds of shells. I love the patterns that these shells have naturally, they are gorgeous. They have nice black, brown, red, and gray patterns. I use them for borders on some of my crosses and frames. You will receive one bag of shells.