Using coins for scale is discouraged as it will require people unfamiliar with them to look up the dimensions or guess, both of which defeat the purpose of the object in the first place. Coins can also reinforce a geographical bias, and some coins' designs are copyrighted.
Ideally, a photograph should include a ruler with the subject (example) or an added scale marking.
SI ("metric") units are the most commonly used worldwide (see meter and centimeter).
I, the copyright holder of this work, release this work into the public domain. This applies worldwide. In some countries this may not be legally possible; if so: I grant anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law.
This image was improved or created by the Wikigraphists of the Graphic Lab (fr). You can propose images to clean up, improve, create or translate as well.
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{{NoCoins}} == Summary == {{Information |Description={{en|1=brown recluse as compared to a U.S.A. penny}} |Source=Own work by uploader |Author=Br-recluse-guy |Date= |Permission= |other_versions=[[Image:Brown-recluse-coin.jpg|thumb|