Homemade venetian plaster Venetian or Marmorino plaster is a style of polished plaster originally developed to mimic the aesthetic of Marble. We have developed our own recipe and technique for this as we don't have access to the very fatty lime (holds a lot of water) that was traditionally used for this special plaster. Base coat - a 3:1 mix is used to level off the earthen wall or whatever substrate you have. This step could be skipped if you have a very flat substrate already. Top coat - 1:1 m