Hesiod’s original Greek account calls Pandora’s container a pithos, not a small box.
A pithos was a large storage jar used in the ancient Greek world for commodities such as grain, wine, or oil. The word better matches the kind of substantial vessel described in the myth than the compact chest suggested by the English phrase “Pandora’s box.”
The “box” wording became dominant through later translations and European artistic retellings. In particular, Renaissance and modern interpreters often represented the vessel as a box, making that image more familiar than the ancient jar. The change is one of vocabulary and visual tradition, not a separate Greek myth.
An amphora was also a Greek vessel, usually with two handles and a narrower body, but it is not the container named in Hesiod’s account. Kraters and kylikes were different types of pottery used for mixing or drinking.