Two glass beads found this season at Nippur may represent the world's oldest extant manmade glass. They were found in sealed floor contexts in association with cuneiform tablets in an Akkadian level at Nippur, Iraq. Both beads were made by fusing bits of barely workable, very viscous glass around a rod. One, a spherical white and olive green bead, was made of a soda-lime-silicate composition. The other, a yellow and bluish green barrel bead with hexagonal cross section, was made of a complex, multi-phase lead-silicate composition. Lead-containing glasses and lead-stannate colorants heretofore have been found to date from late Roman times. The olive green color is caused by about 3per thousand iron oxide; the white bead is opacified by large crystals of a calcium-magnesium-sodium silicate and residual quartz. The yellow and green bead contains a lead-silicate composition and at least four other phases. This bead was probably formed from the vitreous remains of a metallurgical operation (slag) or of a cementation, or slow roasting, process. The colorants in this bead include a lead-tin yellow which when combined with 1-3per thousand copper oxide in solution yields a green color. The appearance varies from translucent to opaque and is explained by the presence of calcium-magnesium-silicate and sodium-calcium-silicate phases. Droplets of a calcium-phosphate-lead-silicate phase are also present. A long heat treatment of both beads is proven by the size and extent of crystal formation, some of which in the spherical bead measure as large as 30 micron in length, showing at least 2-3 full at or just below melting temperature. Some crystals were broken and separated a small amount during forming, showing crystals could not have grown in situ after forming. High viscosity during forming is shown by alignment of crystals parallel to flow combined with some remelting at the edges of the crystals into the glass. Lack of extensive working is shown by the presence of a large miniscus at each end of each bead and by the proximity to one another and alignment of broken crystal fragments. The manufacturing evidence of these beads suggests that they represent an initial stage of glass technology and also that metallurgical processes may have been involved in early glass technology. The microstructure of the yellow and green bead which contains lead-stannate as a colorant is unique; it is unlike that of any later lead-stannate-containing glasses.