What substance looks like brown pellets or crystalline rocks that resemble lumpy soap?

The substance described as looking like brown pellets or crystalline rocks that resemble lumpy soap is indeed Crack. Crack cocaine is a form of cocaine that has been processed to make a rock crystal, and it can vary in appearance. It is typically beige or brown in color and can have a lumpy texture similar to that of soap.

Crack is made by processing powder cocaine with baking soda and water, which then hardens into a rock-like form when cooled. This form allows it to be smoked, producing a more intense and immediate effect compared to other methods of using cocaine.

Other substances listed, like methamphetamines and cocaine, generally have different appearances and forms. Methamphetamines can vary widely but often appear as crystalline shards, while raw cocaine is typically in a white powder form before being processed further. Bazuco, a less common form of cocaine, is known for its poor quality and different morphology, often being a paste or powder rather than solid lumps.