1. A lamp, comprising:an envelope of a quartz glass material defining a discharge space; and
an electric conductor that is at least partly embedded in the quartz glass material of the envelope, wherein the electric conductor comprises:
a surface;
one or more recesses in at least a portion of the surface of the electric conductor; and
flexible dendritic protrusions on the portion of the surface of the electric conductor at edges of the one or more recesses, the flexible dendritic protrusions forming a brush-like structure on the portion of the surface of the electric conductor, wherein an average material density of the brush-like structure is between 20% and 80% of a solid structure of the same material, thereby providing a mechanical flexibility and deformation potential that is substantially higher than that of the solid structure of the same material.