Block Turquoise? LMB cluster Cuff

Hello! Hope everyone is doing well.
I have this cluster Cuff signed LMB Sterling
Could the artist be Larry Moses Begay and is the turquoise authentic?
Thank you


We see a number of these cuffs but never have the artist come into the store selling, not sure what the story is. The turquoise looks like it could be block. That is the hallmark for Larry Moses Begay.