I have not been able to identify this pattern (if you recognize it, please let me know :) but its an older Pyrex cup, of the 400 series; and a larger one, 10 ounce. All a chocolate brown or burnt umber, and has a gold stripe band of tiny diamonds along the bottom.
Bottom of the cup states "489.. 10oz..Trade Mark .. 6.. Pyrex.. (r).. Made in U.S. A.
In good condition with no chips, cracks or rim wear. Color looks wonderful, but when held up to the light there are a few tiny areas of missing paint.