American artist Mary Cassatt, who has received worldwide acclaim for her Impressionist paintings, is hailed on a new 23-cent stamp in the Great Americans Series.

This is the second time Cassatt has been honored on a U.S. stamp. Previously, she appeared on a 1966 adhesive in the American Artists Series, which featured one of her best known works, "The Boating Party."The design of the single-color stamp is based on a 1914 photograph of Cassatt by Armand Delaporte. At the left of the portrait is "USA 23." Her name appears beneath the illustration.

Cassatt was born to a prosperous Philadelphia family in 1844. She surprised friends and family by seeking a career in art and went to study in France. Before long, her work became noticed by such famous French artists as Edgar Degas, who persuaded Cassatt to exhibit her paintings with those of other Impressionists.

The new 23-cent issue meets the postage rate for the second ounce of international surface mail.

First-day cancellations are available in the two usual methods.

Collectors who prefer to affix their own stamps can buy them from their local post office and place on their own envelopes. No remittance is required. At least 2 cents additional postage, however, must be affixed to meet the minimum first-class rate for letters. Send to: Customer-Affixed Envelopes, Mary Cassatt Stamp, Postmaster, Philadelphia, PA 19104-9991. It must be postmarked by Dec. 4.

If you prefer to have the Postal Service affix the stamp, enclose a money order or personal check for 25 cents and send to: Mary Cassatt Stamp, Postmaster, Philadelphia, PA 19104-9992. The Postal Service will add one 2-cent Mary Lyon stamp to meet the first-class rate. The deadline is Dec. 4.

---

Here's an excellent suggestion for a Christmas gift for stamp collectors, young and old. It's the 1987-88 Definitive Mint Set. The 47 stamps in the set represent a cross section of American accomplishment and natural wonders. The set can be bought at philatelic centers, at most post offices and by mail order.

Among the 12 individuals honored on the stamps are three women: painter Mary Cassatt, civil rights activist Julia Ward Howe and educator Mary Lyon.

Other stamps include transportation items, such as a fire engine, railroad mail car and elevator. The birds and the bees are represented as well, in the form of the honeybee, pheasant, owl and grosbeak. The American flag flies against a background of clouds and over Yosemite National Park. Looking down from above, the non-denominated "E" stamp depicts a colorful view of Earth from outer space.

To keep the price of the new set down, the Postal Service does not include the $8.75 Express Mail and $5 Bret Harte stamps. However, the set includes a mail-order form for those who wish to obtain the missing pair and mount them in sections describing those subjects.

To order by mail, send a check or money order for $13.95, plus 50 cents for handling, to: Philatelic Sales Division, Washington, DC 20265-9997.

Also included in the 47-stamp set are the 19 Transportation, 10 Great Americans, four Flag and three Wildlife stamps, as well as three special and two airmail issues.

---

Volume 4 of the just-released "1989 Scott Standard Postage Stamp Catalogue" (covering the non-British countries from P to Z) shows a downward trend in stamp values.

For example, Russia has 373 increases and 2,683 decreases. Turkey shows 392 up and 1,457 down. Romania indicates an increase of just 79 stamps, while 962 moved downward. Spain and Sweden also noted sharp downward trends. One country showing startling price increases is Saudi Arabia.

The list price for Volume 4 in the soft-cover edition is $23, the same as the other three 1989 volumes. The hardcover with gold lettering is $39.95. The catalogs are available at your local stamp dealer.

---

In September, the West Indian island of Nevis released a single $5 stamp to commemorate the fifth anniversary of its political independence from Great Britain, together with its neighboring island of St. Kitts. Nevis is the smaller of the two islands.

The new stamp depicts a map outline of the islands of St. Kitts and Nevis, plus the Nevis coat of arms.

Both islands are members of the United Nations and the British Commonwealth of Nations.