When limestone gets even more squashed, it can turn into travertine or marble. Limestone is also the main way you get lime, which is one of the things you make cement out of. To get lime, you have to burn limestone in lime kilns, and then what is left is lime. In the Middle Ages, people burned most of the statues of ancient Greece and Rome to turn them into lime.
Far as I am aware, CBD oil is not legal in Texas. It is legal for medical use in only Utah, Alabama, Kentucky, Wisconsin, Mississippi, Tennessee, North and South Carolina, Iowa, Florida, Georgia, New York, and Missouri.
The Texas law is similar to those in several other states and is referred to in the industry as a CBD Only Law. These types of laws differ from Medical Marijuana laws in that they limit the amount of THC allowed in medicine. In this case that limit is 0.5%.