Neon John wrote:
On 8 Apr 2017 05:50:33 GMT, (Volker Borchert)
wrote:

John B. wrote:

Loctite 7414 tamper detection paste ?
http://tinyurl.com/m7le3vd

What if the tamperer buys that stuff too?

I've been in the situation a couple of times in my life where
tampering and cover-up was likely. I used fingernail polish to which
I added a tiny amount of a specific mixture of radioactive elements.
Detecting a forgery is as simple as holding a sensitive Geiger counter
to the dot.

Nowadays one might use DNA "ink".

--

"I'm a doctor, not a mechanic." Dr Leonard McCoy
"I'm a mechanic, not a doctor." Volker Borchert