Base portion of a plastic container

A heat-resistant PET container for receiving a commodity requiring one of pasteurization and retort sterilization, said heat-resistant PET container comprising:

• an upper portion defining an aperture and sealable with a closure;
• a sidewall portion connected to and extending generally downward from said upper portion, said sidewall portion defining a sidewall projected area;
• and
• a base portion having a chime section connected to and extending generally downward and inward from said sidewall portion, and a push-up section having a substantially truncated conical shape and with a relatively sharp transition connected to and extending generally upward and inward from said chime section to close said heat-resistant PET container, said push-up section having an outboardmost portion defining a push-up projected area, said sidewall projected area being between 70% and 125% greater than said push-up projected area, and said base portion exhibiting a non-oriented spherulitic crystallization portion approximately equal in size to said push-up projected area and with a crystallinity of at least 30%, a support surface of said base portion being defined substantially entirely by said sharp transition between said push-up section and said chime section.