Dinnerware set JB664 Old Chelsea by Johnson Brothers dated 1902 and how I can tell there trademark?

Is this dinnerware blue and white? If so,you may have a very valuable set of flow blue dinnerware. Johnson Brothers of England made several patterns in flow blue right around the time of the date on yours. Flow blue was made from around 1840 to 1910by several manufacturers and although a great deal was made, whole sets are rare because it was not considered fine china and was used as everyday dishes. Individual dinner plates in excellent condition can be worth upwards of $100 and tea cups with handles intact are worth even more. A whole set though,is worth far more than the sum of its parts so if you have this beautiful blue and white dinnerware, have it appraised for insurance purposes and handle carefully. The last time I found an entire set was 20 years ago and then it was going for about $1500. It has gone up considerably since then. Look on Ebay for an idea of its worth.