It's the earlier shield type. Someone will no doubt be able to deduce the span of years/cutoff for that. But just wanted to hop on and say congratz. What state did you find it in ?
By Frederick Maryland on a site that is both colonial and civil war. Found large pennies, King George coppers and may partner found some dropped 69 cal. three ring bullets in great shape.
The date is on the other side of the coin, the side you say is 'worn almost smooth'. I'll assume, therefore, that you cannot read the date. But what is readable, in part, on this side of the coin are the letters RD VI which is part of the legend: FRD VI, D.G. etc.--a coin of Fernando VI. The coin came in two varieties, but again, you may not be able to discern the differences (one has only 'royal' crowns while the other has an imperial and a royal crown). The first variety was minted between 1747 through 1758; the second variety from 1757 through 1760; on the "worn almost smooth" side.
Don...
PS: Welcome to Treasurenet !!