From test batch AX-598, the bronze version of Iris. Iaso has a high copper content and is capable of yielding bronze metallic exterior lusters. Like Iris, brief but repeated exposure to a small, cool reduction flame produces the best results. The temperature of the beads surface, as well as the intensity, duration, and frequency of reduction determines the final outcome. Variations in the luster can be accentuated by using a very small oxidizing flame to selectively erase portions of the luster, then repeating the reduction process.