One Man's Diamond Is Another Man's Graphite

Diamond and pencil lead (no longer made of lead) are both made of the same element-Carbon.

  Carbon is a unique and important element because it's atoms form four bonds, making it a crucial part of many organic molecules.  

Diamonds are the hardest substance known to man.  Graphite, maybe one of the softest.  There shape is what makes the difference.  The carbon atoms in graphite form one 'flat' shape which allows it to slough off onto your paper with ease.  Diamond's carbons, on the other hand form three dimensional geometric shapes with solid connections, which make it incredibly hard. 

Diamonds are rare, beautiful and expensive.

Graphite is none of those.

But imagine this.  A writer, who dreams of nothing but putting thought to paper (who has no access to the modern conveniences such as the one I am using to write this) who lives vicariously through pencil and paper, who veins flow with graphite, wakes to find that all of his finely sharpened number 2 pencils have been turn to fine diamonds.  He picks one up and begins to write.  But instead of a faint dark line, a tear is formed in the paper.  No matter how carefully, diligently he tries, he shreds every last piece of paper.  The wealth he now possesses is lost on him and he falls into despair.  

On the other hand, the man whose diamonds turn to graphite... That is far to banal and normal an idea to consider.  Monetary wealth is gained and lost every day.