Prominent mineral veins at the "Garden City" site examined by NASA's Curiosity Mars rover vary in thickness and brightness, as seen in this image from Curiosity's Mast Camera (Mastcam).
<p>The image covers and area roughly 2 feet (60 centimeters) across.  Types of vein material evident in the area include:
</p><p>1) thin, dark-toned fracture filling material;
</p><p>2) thick, dark-toned vein material in large fractures;
</p><p>3) light-toned vein material, which was deposited last.
</p>
This image includes annotations identifying each of those three major kinds and a scale bar indicating 10 centimeters (3.9 inches).
NASA/JPL-Caltech/MSSS
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