Re-investigation of the Metamorphic Agates

of the Upper Płóczek, Poland

By: Donald Kasper

 

Features:

·         Shows that the amygdules of Ploczek are formed with substantial chlorite chemistry, an indicator of their metamorphic exposure.

·         Challenges the view that the prasiolite of Poland is green quartz, and is more likely due to beta-quartz.

·         Adds interpretations of many of the specimens lacking in the original text “Agates of the Upper Ploczek, Poland”.

·         A number of zoomed in photos of structures not discussed in the original text, are provided and described.

·         Shows that some of the amygdules of Ploczek are affected by sericitization, the decomposition of feldspar to make illite clay.

 

Halloysite (clay) tubes in a sea of agate.  Iron adsorption to the clay makes the tubes pink.

From Kaczawskie Mtn., Ploczek, Poland.  Photo by Lech Darski.