Sold by piece by weight. Sizes may look similar depending on shape/thickness. Each Lapislazuli stone has been weighted. 

XS: 4g to <7g

SM: 7g to <10g

MD: 10g to <15g

LG: 15g to 20g

Stones cranked up by Jay Essex and Diana R. Anaya (Dianimal)

Pictures taken both in natural and artificial lighting 

Lapislazuli- Works the Pineal Gland (what people call the third eye) down through bottom of neck, and also the Hipothalamus. Helps Metaphysical Vision- best seeing live energy in other dimensions