Half Cents
US Mint produced half cent coins through about 1857, they were around the size of a 25 cent piece now.
I remember gas at 17.9 for regular and 19.9 for 'ethyl'. While in HS I worked at a Skelly station that had blend pumps , the lower grade was Skeltane, the Regular, 50/50, Special and the premium Keotane which had a pretty pinkish color. As kids we could cruise the town for about a buck on Friday nights, still have money for A & W root beer and hot dogs! The station I worked at had one of those 'wash & vacuum' policies - there was always some wise guy coming in getting a buck's worth and expecting the tires checked too. We had to wear white uniforms and bow ties. Amazing how there was a station on about every major corner of the city way back then.....