Thank you ladies!
One thing to consider with my method of setting the branches is the weight. I used Acrylic crystals so they are very light in weight. I placed the branch in the urn and used scraps of cardboard folded/wadded just to prop the branch in the exact position. I then used spray foam (found in a hardware store, ie. Home Depot, Lowe's, etc) to fill the vase. The foam is used by contractors to fill in small areas for insulation purposes. It is packaged in a couple ways. One is just like a whipped cream can and the other is to be used with a gun similar to a caulking gun. The spray foam method will only work if your base/vase is not clear. Otherwise the foam and cardboard will show and will look terribly messy. This is the very reason I opted for the ceramic urn. I suppose, you could position the branch in a smaller container to placed in a larger glass vase/container filled with your desired filler if you really want glass. I thought about this, I decided the most cost effective way would be ONE container with less filler. I recommend experimenting with the spray foam before using it in your actual vase. It expands quite a bit, more than double. Once its on the surface, its there for good so you don't want it to overflow. It takes about 24 hours or more to fully dry. If your vase is deep, apply one layer of spray foam at a time to ensure drying. Otherwise, it can get mushy.
Another material that's commonly used for a project like this is Plaster of Paris. It is a known to be toxic and "can cause cancer" thus the reason why I opted for the spray foam.
Sorry for the long message. I felt it was important to be thurough.
HTH...let me know if you'd like more info.
