Texas is rich in mineral resources, but three of the most prominent are:

1. Petroleum: Texas is known as the "Energy Capital of the World" due to its vast oil and natural gas reserves.

2. Sulphur: Texas is the largest producer of sulphur in the United States. Much of this sulphur is mined from underground deposits.

3. Lignite: This type of brown coal is found in abundance in East Texas and is used primarily for electricity generation.