File talk:Crinoid stem replaced with marcasite.JPG

Image shows a yellow box with label "3.0mm", but it is unclear to me what is being measured. ie there is no span or graduations. Please clarify. And thank you for submitting this image, it is quite fascinating to me.

Thanks for asking. It is a scale bar, so the length of the bar is the indicated measurement. Wilson44691 (talk) 12:23, 17 August 2015 (UTC)