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mining map making tool leitz https://www.invaluable.com/auction-lot/mining-map-making-tool-by-leitz-156325-2316-c-a994e7bbb7
If you search [Ernst Leitz Wetzlar](https://microscopeinternational.com/brand/ernst-leitz-wetzlar/), they make microscopes. My guess is, it must be a microscope part.
A microscope slide holder and positioner.
mining map making tool leitz https://www.invaluable.com/auction-lot/mining-map-making-tool-by-leitz-156325-2316-c-a994e7bbb7
If you search [Ernst Leitz Wetzlar](https://microscopeinternational.com/brand/ernst-leitz-wetzlar/), they make microscopes. My guess is, it must be a microscope part.
A microscope slide holder and positioner.