Baltic amber stone with fossil insect - very rare small aquatic predaceous diving beetle Dytiscidae, probably Laccophilinae or Hydroporinae.
It weighs 0.3 grams. Measurements of stone 12x7x3mm, length of beetle ~ 2.1mm.
I can send digital high resolution picture by e-mail for personal (not commercial) use. Contact me concerning it.
If you which stone can be made into pendant for free. Please check if stone measurements are suitable for you.