CLPEX Chat Board

For those of us that work on the holidays, I thought I'd post this and see what sort of discussion arrises. This was a lift submitted to me this week that came from an ice scraper in a recovered stolen vehicle. After the CSI lifted the print, they examined the surface and noticed the print was impressed in the plastic handle. It appeared as if, when the scraper was being produced, the wriggly lines (ridge details?) were impressed in the mold. Maybe? Take a look at it and let me know what you think.

This could fall into the CLPEX thread "Extrusion or Sprue Marks".

Sprue marks are ripples in material that occur as a molten substance cools inside a mold. They occur on plastics, glass, and even some metals. One LPE even told me of seeing them on the metal of a "Saturday Night Special" revolver he had in evidence. John Torres (San Diego) wrote a paper on sprue marks a few years ago, but I don't think it received wide publication. I have seen some sprue marks that are almost indistinuishable from ridge detail when captured in a lift, as this example was.