Alloy-junction transistor
The germanium alloy-junction transistor, or alloy transistor, was an early type of bipolar junction transistor, developed at General Electric and RCA in 1951 as an improvement over the earlier grown-junction transistor. The usual construction of an alloy-junction transistor is a germanium crystal forming the base, with emitter and collector alloy beads fused on opposite sides.
Source: Wikipedia — Alloy-junction transistor (CC BY-SA 4.0)