How do you instantiate a Procedural Material?

I'm trying to set up a basic Procedural Material, and I am having no luck. The docs and a simple example for the class are here: http://docs.unity3d.com/ScriptReference/ProceduralMaterial.html but I can't find any tutorials or other examples online. This class isn't deprecated is it?

Here's the inspector for a single cube on which I've attached a Proc Mat Handler script:

The script (Proc Mathandler) is exactly as copied from the docs:

 using UnityEngine;
 using System.Collections;
 
 public class ProcMathandler : MonoBehaviour {
 
     public string floatRangeProperty = "Saturation";
     public float cycleTime = 10;
     public Renderer rend;
 
     void Start() {
         rend = GetComponent<Renderer>();
     }
 
     void Update () {
         ProceduralMaterial substance = rend.sharedMaterial as ProceduralMaterial;
 
         if (substance) {
             Debug.Log("Found a substance");
             // Make the property go up and down over time
             var lerp = Mathf.PingPong (Time.time * 2 / cycleTime, 1);
             substance.SetProceduralFloat (floatRangeProperty, lerp);
             substance.RebuildTextures ();
         }
         Debug.Log("Did not find a substance");
     }
 }

Unfortunately, substance is always null. rend.SharedMaterial returns the proper Material, but when I cast it to a ProceduralMaterial, something goes wrong.

Anybody know what that is?

Thanks, Sam