Although many people prefer a simple white cup for tea leaf reading, there are also traditions concerning the positional placement of the leaves in the cup, and some find it easier to work with marked cups. Beginning in the late 19th century and continuing to the present, English and American potteries have produced specially decorated cup and saucer sets for the use of tea-leaf readers. Many of these designs are patented and come with instructions explaining their mode of use. Some of the most common were those that were given away with purchases of bulk tea.
There are dozens of individual designs of fortune tellers' cups, but the three most common types are Playing Card cups, Symbol cups, and Zodiac cups.
Symbol cups - These sets are decorated with between a dozen and fifty of the most common visual cues that can be found in tea leaves, often numbered for easy reference and supplied with an explanatory booklet. The symbols are generally displayed inside the cups, but there are also sets in which they decorate the outside or appear in the cups and on the saucers. (Information courtesy of Wikipedia.)