When trends catch on in accessories — whether spikes, agate, or lockets — everyone’s jewelry collection can start blurring together. Among a sea of copies, it’s nice to have accent pieces that set themselves apart. Kathryn Bentley’s Dream Collective necklaces have more to them than they seem: The multicolored “sequins” are cut from old records and strung on an antiqued brass chain. Sometimes a rock and roll reference doesn’t have to be quite so overt.