Formation of black opal in the pegmatites from Volyn (Ukraine) – an example for interaction of silica with organic matter

Franz, Gerhard; Khomenko, Vladimir; Chornousenko, Vsevolod; Zeh, Armin; Schiperski, Ferry; Gouzy, Simon; Gernert, Ulrich; Nissen, Jörg

doi:10.5194/ejm-38-305-2026

Articles | Volume 38, issue 3

https://doi.org/10.5194/ejm-38-305-2026

© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/ejm-38-305-2026

© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 38, issue 3

Research article

|

22 May 2026

Research article |

| 22 May 2026

Formation of black opal in the pegmatites from Volyn (Ukraine) – an example for interaction of silica with organic matter

Gerhard Franz, Vladimir Khomenko, Vsevolod Chornousenko, Armin Zeh, Ferry Schiperski, Simon Gouzy, Ulrich Gernert, and Jörg Nissen

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