Northstar Hyacinth boro glass is a lush fully opaque faux purple. It is great for blown work and thin stringer application. It is heat and flame sensitive so it must be heated up slowly to prevent boiling. Once it glows red, Hyacinth will take heat well. Because of its intensity it is sensitive to reduction. If the flame is not oxidizing enough gray and brown streaks will develop on the surface of the glass. Try it with a layer of NS-032 Violet for a deep purple effect!