This is a Sheaffer Snorkel Sovereign in Pastel Blue or Aqua c. 1952-1959. Pastel Blue / Aqua was one of the original Snorkel colors introduced in 1952. The Sovereign has an open 14 karat gold nib with two-tone mask, possibly palladium (similar to earlier Feathertouch nibs), polished stainless steel cap with five engraved panels and plastic barrel and gold-filled clip stamped "SHEAFFER'S." The cap panels are a set of two straight lines with a dashed and diamond line between. Colors produced were black, burgundy, pastel gray, pastel blue (or aqua), pastel green, buckskin tan, vermilion, and sage green. In 1955, the Snorkel Sovereign sold for $12.50 and the matching pencil was $5.25.