Diamonds without lab reports will be even more commonly over-graded. When placing the order, you, the buyer must be adamant on the importance accurate grading. If the dealer clearly understands this, but still sends over-graded diamonds, you must strongly consider ending your business relationship with that particular source. When you achieve a level of reputation in the trade, diamond dealers will be many, so the loss (or dismissal) of one will be insignificant. It is important to handle disagreements in a calm, professional manner, so as to not give the dealer an excuse to spread negative feedback against your good name.