Micrograph of ductile iron; black nodes of spheroidal graphite are surrounded by white areas of pure iron
<a href="//commons.wikimedia.org/w/index.php?title=User:Hb_tuw&amp;action=edit&amp;redlink=1" class="new" title="User:Hb tuw (page does not exist)">Hb tuw</a>
<span class="int-own-work" lang="en">Own work</span>