But I’ll begin with an overview. Clear glass is traceable, most often, to hard liquor and white-wine bottles—the latter abundant in the warmer months here in the East, tossed or fallen from our decks and pleasure boats, left behind after our beachy celebrations of sun and solstice. The browns are attributable to brewery trash—Buds, Miller Lights, and the common, local, sometimes historically significant varietals (National Bohemian in Baltimore). Stellas, and other upper-end finds, produce chips the color of spectacular Nordic eyes, original-flavor Sucrets, jade beads, backlit aloe. The blues are most highly prized (see recent New Yorker cartoon with happy couple on beach, strolling the shore, hand in hand, him saying, “You are my blue beach glass”). Where might the blue originate? Milk of Magnesia, classy vodka, Vicks VapoRub bottles, all crashed against jetties or reefs on their journey to shore. And, too, there’s the chance of finding a pressed blue letter or word, indicating a truly old liniment jar, or a blue iodine bottle’s thickened corner worn to a platelet, a sort of halved marble, its center swirl gutted and smoothed.