Dye Stain
Gentian Violet
Common name: Crystal Violet
DISCLAIMER: Water soluble tape should not be processed with Gentian Violet.
1. Select an application method.
Tray immersion: Submerge item in Gentian Violet for 1 – 2 minutes. Tweezers or tongs may be used to help draw tape through the Gentian Violet solution.
Brush application: Brush Gentian Violet onto surface using a camel hair brush and leave for 1 -2 minutes.
2. Rinse with cold tap water for 30 seconds.
3. Allow item to air dry.
4. Ridges will develop a purple color and can be captured using 1:1 photography.
5. View ridge detail using ambient light or a forensic light source in the 505 – 570nm range with red googles.
6. Capture ridge detail using 1:1 photography and a red barrier filter (when applicable).
View under
Ambient or 505 - 570nm
Goggles / Filter
Red
Development Color
Purple
PRO TIP: Gentian Violet is also effective on grease- and oil-contaminated surfaces!
REFERENCES
Bramble, S. K. et al. (2000). Deep Red to Near Infrared (NIR) Fluorescence of Gentian Violet-treated Latent Prints. Journal of Forensic Identification. 50 (1): 33 – 49. Retrieved from https://www.researchgate.net/publication/282675666_Deep_red_to_near_infrared_NIR_fluorescence_of_gentian_violet-treated_latent_prints
FBI Laboratory. (2000). Gentian Violet. Processing Guide for Developing Latent Prints. p. 12. Retrieved from https://archives.fbi.gov/archives/about-us/lab/forensic-science-communications/fsc/jan2001/lpu.pdf
Ohio BCI Crime Laboratory. (2020). Procedure: Adhesive Surfaces. Latent Prints Methods Manual. Retrieved from https://www.ohioattorneygeneral.gov/Files/Law-Enforcement/BCI/Laboratory-Division/BCI-Latent-Print-Methods-Manual.aspx