You asked: "What are they from/ for??"
Dave answered the "from"... I'll give you the "for"
With some embarrassment I must confess that there are a few ego-maniacs that pursue monograms selfishly.
In fact - it seems some folks are motivated by little more than some self-serving victory and personal gain.

Fortunately there are OTHERS that find inlaid and monogram chips to be colorful, affordable, fun and historic!

But before you leap into a world of vintage clay
or striking designs and colors
and BEFORE you start your quests for
R's - for O's - and B's ...
I'll share with you the "darker-side of monograms".

I was hopelessly "Z-less" and thought I'd NEVER "Z" my "suZanne".
Desperate and acting in sheer frustration,
I tried WHINING, PLEADING, BEGGING and "JILLING"
It worked... I found my "Z"!

Have fun - Happy chipping - and believe in "Happy Endings"!