Watch List notes:

Agrippa (grandfather of Caligula). AE As (11.86 g). Rome, under Gaius Caligula, AD 37-41. M AGRIPPA L F COS III, head of Agrippa left, wearing rostral crown. Reverse: S C across field, Neptune standing facing, head left, holding small dolphin and trident. RIC 58; BMC 161; BN 77. Glossy dark olive-brown patina with attractive light mottling. Superb Extremely Fine. Estimated Value $2,000 - UP
Perhaps more than any other emperor of Rome, Caligula honored his family on his coinage, both living and deceased members. Besides his surviving sisters, amongst those so honored were his great-grandfather Augustus, his grandfather Agrippa, his father Germanicus, and his mother and his two brothers, Agrippina I and Nero and Drusus Caesars, the latter three succumbing in the family's contest for power against Sejanus, Tiberius's notorious Praetorian Prefect. This beautiful coin remembers Caligula's grandfather, Agrippa, the close friend of Augustus and his star general.
Ex Roma XIX (26 March 2020), 779; Ex Gorny & Mosch Giessner Munzhandlung - Auction 138, 7 March 2005, lot 201.