Why is this called Elevation 9,640?

Because that was the elevation of the highest point on our mountain property. Our silver mining claim (aptly named “The Colorado”) went up one side of the mountain and down the other; split equally in half with one side in Gilpin County and the other in Clear Creek County.  A stone marker was placed in the middle of our property long ago by surveyors who etched the elevation and county names into the stone.