Shreve, Crump & Low

Not for nothing has this Boston institution been a favorite among other Boston institutions (Isabella Stewart Gardener and Ted Williams, for starters) since it opened in 1796. The store is packed with sapphire rings and ruby and diamond necklaces that shine with all the quiet wattage of a chandelier. Want to cut back on the bling? Go for any of the elegant diamond-encrusted pearl pendants—heirlooms in the making, every last one.