Protips:
Allow the diamonds to do the cutting: Do NOT over-pressure stones against the lap. Use adequate water, and reasonable (not excessive) speed and pressure.
Use this lap in grits larger than 600 for gross shaping, at 600 for primary cutting, and at finer grades for prepolishing.
When this lap comes to the end of service life it will begin to create scratches or sub-surface damage due to diamond shedding (which will be accelerated by using too much pressure).
Once this begins, the lap should be retired from lapidary service but can still offer many years of service as a diamond knife or tool sharpener: Comparable honing stones cost as much as the lap did when new. So, repurposing or gifting the lap for this use fairly doubles the value of your investment.
