Eisch Peacock Feather (Pfauenage) Vase

Made by Eisch Hutte, (or Eisch Works) Germany, probably late 60s to early 70s.

Eisch glass was established by Valentin Eisch and the factory's work is always acid etched with Eisch or Eisch Hutte. There is a lot of misinformation about this glass, as Valentin's son, Erwin Eisch, became one of the world's great glass artists in late 2oth century, and many claim all Eisch glass as his. Although Erwin is known to have had some design input at the family factory, his own hand made works have his own signature engraved on his glass. So any Eisch glass sold with the acid etched mark is not by Erwin.

This vase is almost impossible to photograph well enough to show it's style.
It's made from a very deep cobalt blue glass with clear and yellow bubbles (almost like blisters) which are layered small at the base, then elongate through the neck and compress again at the rim. The bubbles actually look like milk opals. Whole vase is quite thickly cased in clear.
It is a very subtle yet complex piece of glass. And yes, is a bit like a peacock's feather.
I have seen the Pfauenage decor on small and large vases, pitchers and bowls, and in blue, green and red.
This vase is one of the larger at 170mm.