Seems it&#x27;s possible - <a href="http:&#x2F;&#x2F;www.concretenetwork.com&#x2F;concrete-color&#x2F;charts.html" rel="nofollow">http:&#x2F;&#x2F;www.concretenetwork.com&#x2F;concrete-color&#x2F;charts.html</a> - presumably it&#x27;s either expensive or difficult to work with so it&#x27;s not used often.