(read how to identify your stamp below)
You will notice the stamp to the left tends to be more of a carmine color than the stamp on the right. If the stamp does not have an embossed grill (shown below) and errs towards the carmine of the left stamp then click here.
If the stamps color errs towards the carmine of the stamp on the left and has an embossed grill (an example is shown below) click here.
This stamp was reprinted in 1875 and it can be viewed by clicking on the numbers 167-177. These are all accounted for, so you will not own this.
The stamps color was changed to purple in 1888. The purple version can be found by clicking the numbers 215-218 on the menu to the left.
Is your stamp purple?
Then you have Scotts #218