Lumadro

Field guides draw every bird the same size on the page, periodic tables print the same 118 boxes, and gem charts tell you a stone is "heavy" without saying what that means. We make the version we could not buy: a chart where the drawing is the measurement.

Every figure comes from a published source that permits commercial use, and the citation is printed along the foot of the chart rather than hidden on a website. Bird weights come from AVONET, a peer-reviewed database of bird measurements. Element densities come from PubChem, published by the US National Library of Medicine. Gemstone hardness and specific gravity come from a US Geological Survey publication. Nothing is estimated: where a figure has never been measured, the chart says so.