Ptolemy I Soter (Savior), (born 367/366 BC, Macedonia—died 283/282, began as a Macedonian General and Body Guard to Alexander the Great. He was Satrap of Egypt after Alexander’s death. He pronounced himself King and ruler of Egypt in 305BC.  He was the founder of the Ptolemaic line of Kings and Queens which reigned longer than any other dynasty after the Alexandrian empire split.  The last ruler of the Ptolemies Cleopatra VII would be defeated by Romans in 30 BC. 
After assuming the royal title in 305/4 BC began to issue gold coins bearing his own portrait with the inscription on the reverse: 
ITTOVEMAIOY BA£IVEQ£ (The Coins of Ptolemy the King)
Ptolemy I Soter King 305-285BC Gold Pentadrachm Alexandria 17.79g NGC CHXF * 5/5 Strike 5/4 Surface FINE STYLE 
Obverse- Diademed Head of Ptolemy facing right with aegis around neck. 
Reserve- ITTOVEMAIOY BA£IVEQ£ Eagle with closed wings standing on thunderbolt. 
Struck on a large flan with possibly the best possible centering on both sides. Awarded 2 special designations: Fine Style for advanced artistry and design quality, and the Star designation for above average eye appeal and originality. 
The Pentadrachm was the second largest gold coin meant for circulation and quite possibly one the rarest denominations to survive. It was equal to 5 Phoenician- Ptolemaic Drachms or 60 Silver Drachms when making payments. 
Ptolemy I coinage were made rare by his son as successor Ptolemy II. An ancient Egyptian document was found written in 268BC that explained that an official order was given to recall all old worn Octodrachms and Pentadrachms struck under Ptolemy I. And replace them with freshly struck gold coins of Ptolemy II in all denominations. 
This coin was recently sold to a savvy collector.