hematine
/ˈhiːmətiːn/
noun
- A dark blue or purple dye obtained from logwood, used for staining in microscopy and as a textile dye.
- Historically, hematine was extracted from logwood trees and used to dye fabrics a deep purple color.
- In the lab, hematine solution turns blue when mixed with certain metal salts.
- The biologist used hematine to stain the cell nuclei for better visibility under the microscope.