Came here to say that, I can not remember the exact details but I read somewhere there is an additional chemical complexity to emotional tears as opposed to practical flushing tears that thickens them such that they flow more slowly down the face and so are visible for longer.
Came here to say that, I can not remember the exact details but I read somewhere there is an additional chemical complexity to emotional tears as opposed to practical flushing tears that thickens them such that they flow more slowly down the face and so are visible for longer.
I was looking for a good source for that (I have heard the same thing) but found this instead which is still helpful.
https://www.sciencedirect.com/science/article/pii/S2666956022000290
There is this article too
https://pubmed.ncbi.nlm.nih.gov/19568753/
Emotional tears have an higher concentrations of proteins that make them stick longer on the face.