Unlike Ponzi schemes, financial pyramids are not product-based and driven by ideas of deposit returns. Known for their unrealistic gain promises of 20%> of returns on monthly basis or so.
Just like Ponzi schemes, financial pyramids rely on tier-based levels of investment. Those, who are closer to the top of the pyramid most likely don't lose anything. Known pyramids are: Bernard Madoff LLC, MMM, some of cryptocurrency schemes and other pyramids that solicit people to invest in chains.