The present disclosure discloses a method of producing an anatomical phantom of an anatomical part having components of different density. The method includes providing a mold of an anatomical part, providing a mold having a size and shape corresponding to a first constituent of the anatomical part. A first liquid is place into the constituent mold and frozen which is placed into the larger anatomical mold and supported in a location corresponding to an actual location of the part in an actual anatomical part. The larger mold is then filled with a second liquid, which forms a gel after a freeze/thaw cycle, to encase the frozen first liquid in the second liquid and the temperature is dropped to freeze the second liquid. The combination is then thawed to produce an anatomical phantom of the anatomical part having a continuous seam between the first constituent part and a remainder of the anatomical part represented by the polyvinyl alcohol based gel. The first and second liquids have a composition such that upon undergoing one freeze thaw cycle, products resulting from the freeze thaw cycle have different densities approximating different constituents of the anatomical part with the second product being a gel encapsulating the first product.