#3 - a 6” x 1 ¼” that was hidden in oil/dirt in a cheap lot of stones. Have not used much yet. Crack(?) in the coticule side I can’t tell if someone filled or manganese line. No crack/fissure there and almost reflective in the light (see pic). Seems more like filled that manganese to me. Such a pure creamy color I suspected synthetic...but the back side of the stone where glued to BBW isn’t square or perfect. Opinions on natural vs synth welcome.