Heartglass Charm of the Borrowed Pulse

This charm is a thumb-sized teardrop of translucent green crystal caged in thin gold vines. A single silver vein runs through its center like a leaf stem, and within the glass a tiny red pulse beats as though a heart were trapped inside. When held near living flesh, the charm grows warm and hums faintly, and dew-bright motes gather around any potion stopper or vial it touches.