One cow's excrement is one man's fine writing instrument.
At least it is for John Lopez, 42, who began making his South Texas Cow Patty Pens six years ago with local, natural materials.
He perfected the process through trial and error. The end result: flecks of brown suspended in a clear plastic, looking almost like wood from a distance.
His original brand name for the pens included a vulgar barnyard term, but it offended customers and other vendors at craft shows, so he retreated to the safer "South Texas Cow Patty Pen." The finished product goes for $45.