Prev Next


  • Aerial view: The view looking down on something from above, as if from an airplane
  • Cast: a 3D example of a model created when a mold is filled with a liquid material that hardens and is then released from the mold
  • Cavity (depression): the area that is pushed down in a mold which is the reverse image of the model
  • Class evidence: Evidence that cannot positively identify someone, such as shoe prints since many people wear the same kind of shoes. Other examples: blood type, soil and glass
  • Curing time: the period a material requires to fully cure (dry) in order to be successfully de-molded
  • Impression: to push a model into a soft material. This creates a cavity in the mold
  • Model: the original object one is trying to recreate (tire piece/tread pattern)
  • Mold: the area that carries a negative or reverse impression of the original model and is used to capture the details of the model
  • Mold-release agent: a spray, liquid or powder used to prevent sticking of the model in the cavity
  • Physical evidence: Evidence that is part of an object and shows that a crime has been committed. Examples: weapons, handwriting and carpet
  • Plaster of Paris: a white powder made from a mineral (originally found outside of Paris, France) called gypsum. When mixed with water, it forms a paste and then hardens to a solid. This mixture creates a chemical reaction that releases energy in the form of heat
  • Tread: Raised design on the tire itself