NS-001 Of the four shades of cobalt blue Northstar produces, this ranks as the second lightest. NS-001 is well suited for small blown work, as well as sculpture when a medium transparent blue is desired. NS-001 Cobalt Blue can take a lot of heat and can be worked in a wide range of flame settings. Though the color is extremely intense, be sure to stay out of reducing flames to prevent any dulling or graying. For additional information about working NS-001 Cobalt Blue or other cobalt blues refer to Northstar Newsletter 16.