From Fallen London Wiki

12.5<style data-mw-deduplicate="TemplateStyles:r1245547">html[data-flw-theme="dark"] .mw-parser-output .flw-echo{filter:invert(70%)sepia(4%)saturate(1224%)hue-rotate(1deg)brightness(102%)contrast(89%)}html[data-flw-theme="light"] .mw-parser-output .flw-echo{filter:invert(3%)sepia(5%)saturate(6260%)hue-rotate(351deg)brightness(96%)contrast(99%)}.mw-parser-output .flw-echo{vertical-align:-8%;margin:0 -6px}</style><a href="/wiki/Penny" title="Penny"><img alt="E" src="/w/images/6/68/Icon-echo-black.svg" width="23" height="15" class="flw-echo" /></a> actually; Stuivers are valued at 0.05<link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1245547"/><a href="/wiki/Penny" title="Penny"><img alt="E" src="/w/images/6/68/Icon-echo-black.svg" width="23" height="15" class="flw-echo" /></a> , making this (rightfully, given how cool it is narratively) a pretty valuable item