Carnelian 2" Skull

Carnelian
A stone of courage
Activates the lower chakras
Grounds and anchors you in the present reality
A stabilizing stone with high energy
Stimulates creativity, vitality and motivation
Improves analytic abilities and clarifies perception
A powerful protector against envy, rage and resentment
Calms anger and banishes emotional negativity
Stimulates the metabolism
Placed near the front door invokes protection and invites abundance
 
Crystal Skulls
Help connect with spirit guides, ancestors, spiritual teachers and ascended masters
Can provide protection and healing when worked with
Can connect with ancient knowledge, as they are record keepers
Assist with channeling guidance
Can be held during meditation
You can also use them as part of a crystal grid
They each have their own personality and when asked, will give you their name
This is just a snippet of information.  There are many good books and articles to provide more information