Cement Stones

That may seem like a contradiction--cement stones--but I have noticed many home-made stones around.
On last weeks posting on our sister blog, the Cemetery Divas I mentioned now odd it was there there were so many cement tombstones there.
First there was my paternal great-grandfathers. It is well made, with curved corners and strong enough to stand upright, but the letters appear to have been carved in with a nail or something similar. Another unusual feature of Grampa Jesse's stone is that it was painted silver. I really cannot give you any history of the stone. Since he had divorced his wife, my Great Grandma Carrie, my grandmother/his daughter wouldn't have much to do with him. He is buried in Curtice Cemetery and is in the northern part of the county and while far from my branch of the family, there were some other Crosses in the area.
The puzzling thing though was that there were other stones of similar shape and size as GGrampa Jesse's. Another almost identical, also painted silver but with molded letters. In the picture below, the more ornate stone for "Thomas" also apears to be cement and painted silver.
There were several others, some pictured on the other blog from last week that also appear to be cement.

Is this a widely used means of making stones? Can anyone tell if they have seen a lot of them in the same area? Especially as well done as the Thomas stone. It has the embossed symbol below the name and is very well made. I wondered if it could be just because the area where this cemetery is located was near a community (now abandoned) that made cement, being near marl pits and sand.

Of course, there are other reasons for cement stones. This is a stone made by my father for his aunt. She was Uncle Bert's second wife, and the surviving son never did get around to putting a stone on her grave, just leaving the little aluminum marker. So Dad made her this one.
This was a much simpler stone, although Dad did find wooden letters and inlaid them into the cement. Although they have mostly rotted away, you can still pretty much make out the date as well as the years 1895 to 1981.