Fig. 37.-SE image of a HF-etched K-feldspar fragment. Left image is of (001) cleavage fragment

Lamellae greater than ~100 nm in width are decorated by pairs of etch pits. Narrower lamellae have few or no etch pits. The platelet-rich area (left) and some of lamellae are completely free of etch pits. Right image is of (010) cleavage fragment. Pairs of nm-sized etch pits with a distinctive two-fold symmetry straddle the albite lamellae. (SE image and description is taken from Lee et al., 1995).