Petrographic microscoope and SEM images of flat-polished thin sections of chert / carbonate chert immersed in various

solutions analogous to ASTM C 289

Control NaOH KOH

Ca(OH)2 K-Ac K-Ac & Ca(OH)2

Plane polarized transmitted light images

Control NaOH KOH

Ca(OH)2 K-Ac K-Ac & Ca(OH)2

Crossed polarized transmitted light images

Control NaOH KOH

Ca(OH)2 K-Ac K-Ac & Ca(OH)2

Epifluorescent images

Control NaOH KOH

Ca(OH)2 K-Ac K-Ac & Ca(OH)2

Elemental maps for silicon

Control NaOH KOH

Ca(OH)2 K-Ac K-Ac & Ca(OH)2

Elemental maps for sodium

Control NaOH KOH

Ca(OH)2 K-Ac K-Ac & Ca(OH)2

Elemental maps for potassium

Control NaOH KOH

Ca(OH)2 K-Ac K-Ac & Ca(OH)2

Elemental maps for calcium

SEM images of powder mounts of chert / carbonate chert immersed in various solutions analogous to ASTM C 289

Control

NaOH

KOH

Ca(OH)2

K-Ac & Ca(OH)2

K-Ac