Juvenile T. rex tooth?

[bcfossilcollector]

Hi. I could use some help identifying this tooth which, by the way I'm considering purchasing. The seller claims it is from a juvenile Rex and was found in the Hell Creek formation. I think it looks good but am not experienced enough to tell for certain. Thanks for any help. 

[Troodon]

Looks like a Rex tooth what size is it.

[bcfossilcollector]

According to the seller it is 9/16s of an inch. 

[Troodon]

Thanks definitely a juvie nice tooth

[bcfossilcollector]

Thanks Troodon!