☽ Inverted pentagrams ☾
The pentacle (or pentagram) is a five-pointed star surrounded by a circle. The branches of the pentagram symbolize the spirit and the elements (water, earth, air, fire) connected by the great whole symbolized by the circle. When the pentagram is turned downwards, as it is here, it is considered that the spirit is symbolically turned towards the earth, and thus, by extension, towards materiality.
The inverted pentagram was also a symbol of protection that can still be found in some religious buildings (Amiens Cathedral, Basilica of the Sacred Heart of Montmartre...). It was also later taken up by Satanism, considering that if the spirit is turned towards the earth, it is also turned towards what is under the earth, in other words hell.