I use oil based gesso to apply relief to a panel, artists such as Margaret McDonald used a similar type of relie. I use different types of application, trailing, and layeri, and, I can also add materials, for example sand, and I can also embed, it is such a brilliant medium.
As you can see from the image above, I have trailed on the gesso, which drys rock hard, and allows for another dimension to add to the panel. I make my own oil based gesso, base on an historic recipe.