Most people can identify this one: The saucer magnolia (Magnolia soulangeana) does very well in these parts and an increasing number of cultivars have come on the market offering a range of colors from the common pink to a deeper purple.
Seen here are the two spectacular magnolias that frame the John Carter Brown Library on the main green at Brown. Often described as a small tree, that is a relative term in horticultural circles (they are small compared to oaks and poplars).
Saucer magnolias can reach up to 30′ in height so plant them where they will have room. They are generally used as an accent plant in the landscape with handsome bark color and foliage. It grows into a lovely open vase shape and requires no pruning other than removal of deadwood and crossing branches. If you like poodles and lollipops — this is not your tree.
One caveat: The large, fleshy petals hate a heavy downpour. Rhode Island tends towards rainy spring weather which can sometimes spoil the show. Still a worthy tree for your landscape.