Curiosity has photographed these strange forms on Mars on July 24, 2013
Photo listed here on the official website:
The photo that interests us here. The coordinates are: Right MastCam, SOL 343. Photo taken on July 24, 2013 and posted on the official site on 26 July 2013. I circled in red the strange shapes, and I zoomed in:
ANOMALY ON MARS: PHOTOS:
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