Glidden Points stand out on raw-bar lists for their size, crispness, brine, deep cup, and rock-hard shells. What I always notice is their weight. Hold a Glidden Point in one hand and a different oyster in the other and you will immediately notice the heft of the Glidden Point. Both the shell and the meat have a density that comes only from slow growth in cold water: Glidden Points are grown forty feet deep in the frigid Damariscotta, making them perhaps the deepest- and coldest-grown oysters on the East Coast. They are four years old when they reach market size, unusually rich and springy. The shells are a natty white and black. The greenish algae that colors many shallow-water oyster shells can’t thrive at the depths where Glidden Points grow.