Matte Met Blue Green Iris SB18-2064 Miyuki Cube 1.8mm - Use these tiny cube beads to add a fun angular look to your bead weaving and stringing designs. Miyuki cubes work well in brick stitch patterns because of their flat sides. These Japanese seed beads come in a variety of colors and finishes. Miyuki Cube beads measure 1.8mm and come in a tube of approximately 720.