Check this out!
Lots of possibilities with this technique! Could add shading and details to a piece without getting any major ‘depth’. Great for ‘branding’ your work. Imagine cutting puzzle sets, and drawing on them after the fact.
I’m quite intrigued with this! Next grocery store run, I’m stopping by the pharmacy for some Ammoniumcloride!
Heck, don’t even need a laser. 
Thanks. This looks like another great bit of fun 
Rabbit hole! Rabbit hole!!! 
In English speaking countries it’s called ammonium chloride.
And for more comments see this post from about a year ago:
Thanks! I swear I did a search before posting. (but I searched it as one word as in my title)
Definitely a fun rabbit hole!
WOW! saved.