For most people who purchase a mezuzah, the beauty of the mezuzah case is of particular importance.  In reality what is more important is the actual kosher mezuzah parchment blessing that the case contains.  The true kosher blessings should be written on parchment.  The parchment should be prepared from a kosher animal.  The process of  preparing this animal skin comprises of soaking, cleansing and leaving it in lime for an extended period.  From this stage the skin is then stretched, placed to dry under certain temperature and only the suitable layer is used  for writing on. 

The ink used is of a special kind and so is the pen which generally comes from a kosher bird.  The actual writing must be done perfectly, without the slightest flaw which means that the letters may not touch each other.  This explanation is only a summary of the process involved in the making of this blessing and it is truly an admirable one in which so much attention and care is placed into following the Torah which instructs in Deuteronomy 6:4-9 ,  the following in translation , "And you shall write them on the doorposts of your house and on your gates".

          Kosher parchment blessing