Marble busts made by Houdon were exhibited in Paris in 1789

What should my painting sell for? Antiques appraisers are not licensed like real estate appraisers, but there are art appreciation courses in universities, degrees in fine art and appraisal associations that require members to pass tests. Some work in an art gallery, auction company or museum and learn to appraise through experience.

A treasure can be found in a house sale, resale shop or charity auction; however, the White House had an eglomise desk that was a reproduction. The Ford museum bought a fake 1620 “Brewster” chair made deliberately to fool a museum “expert” in 1969. And sometimes a real treasure is thought to be a reproduction.

A pair of marble busts made by Jean-Antoine Houdon (1741-1828) were exhibited in Paris in 1789. They were bought in Paris in 1926 by an American diplomat, mentioned in a reference library in 1932 and passed down in the family of the American diplomat.

They were “lost” until a Cottone auction in 2019. The pair sold for $1.475 million. Where had they been? The last record was in a 2000 house sale run by a New York auction house that had an appraiser who did not realize that they were busts by Houdon.

The 11-inch-tall busts are signed and dated, 1788 and 1789. One is Jean-Jacques Rousseau, the other Georges-Louis Leclerc, Comte de Buffon. The busts must have been in the diplomat’s house and then a relative’s for 77 years after the collector who bought them in Paris died in 1941.

Q: We recently had a family member pass away who was a collector of Mary Gregory. Before I give this glassware away, can you tell me if there is a demand for it. If so, about what price range collectors are paying?

A: Mary Gregory glass is colored glass or clear glass decorated with white figures. It watsn’t made by a woman named Mary Gregory, as is sometimes believed. The first glass known as Mary Gregory was made in Bohemia about 1870. Figures were usually children at play. Similar glass is made today in the United States and other countries. Children standing, not playing, were not pictured until after the 1950s. It was thought Mary Gregory worked at the Boston and Sandwich Glass Company but that’s not true. Westmoreland Glass Co. began making the first Mary Gregory-type decorations on American glassware in 1957. The pieces had simpler designs, less enamel paint and more modern shapes. Bohemia, France, Italy, Germany, Switzerland and England also made this glassware. It is popular with collectors and sells at low prices. Pieces sell at auction and online for under $20 to a few hundred dollars. A blue decanter was $12, a cranberry sugar and creamer set was $100, and a 17½-inch cranberry glass vase was $600.

Q: We’re looking to sell an old square piano that must be at least 100 years old. Can you tell us where a good place to sell it would be?

A: Square grand pianos, sometimes called box pianos, have a rectangular-shaped cabinet and strings that run from side to side, rather than front to back like the grand pianos made today. They were made in Europe beginning in the 18th century and were made in the United States by the beginning of the 19th century. Square grands were the most popular piano sold until about 1890. They are hard to sell now. The strings, hammers and leather or felt covering on the hammers deteriorate with age. The pianos can be hard to tune because they have differently shaped tuning pins and require different tuning equipment. Some people will buy an old square grand, remove the insides and use it as a desk. If the piano is in good, playable condition, contact a music store that sells used pianos to see what they are selling for in your area. If you want to tackle it on your own, try a local online listing source, because it’s expensive to ship.

Q: My mother-in-law gave me a porcelain hatpin holder with eight hatpins in 1947. It’s about 5 inches high and has two poppies painted on it. The bottom is marked with a star above a wreath with the initials “RS” inside it and “Germany” below. I want to pass it on to my granddaughter. How old is it? What is the value?

A: Hatpin holders were made when hatpins were fashionable from about 1860 to 1920. The pins were 6 to 12 inches long and were used to hold a large hat on top of a woman’s hair. The pin tops were made of porcelain, glass, gold, silver, rhinestones, gemstones and other materials and are collected today. Your hatpin holder was made by the Reinhold Schlegelmilch Porcelain Factory, which started in Suhl, Germany, in 1869. The company had a branch in Tillowitz and moved its operations there in 1932. The factory made decorated and undecorated porcelain. Much of it was exported to the United States. This mark was first used about 1914, so your hatpin holder was probably made between 1914 and 1920. Hatpins are collectible, and costume jewelry pins sell for $20-$50. Real gold hatpins can sell for $200-$300. Hatpin holders sell for about $100 to $200.

Tip: A vase that has been drilled for a lamp, even if the hole for the wiring is original, is worth 30% to 50% of the value of the same vase without a hole.

Terry Kovel and Kim Kovel answer questions sent to the column. By sending a letter with a question and a picture, you give full permission for use in the column or any other Kovel forum. Names, addresses or email addresses will not be published. We cannot guarantee the return of photographs, but if a stamped envelope is included, we will try. The amount of mail makes personal answers or appraisals impossible. Write to Kovels, The Daily Herald, King Features Syndicate, 628 Virginia Dr., Orlando, FL 32803.

On the block

Current prices are recorded from antiques shows, flea markets, sales and auctions throughout the United States. Prices vary in different locations because of local economic conditions.

Cabinet on stand, mirrored, cut glass diamonds, 2 doors, shelves, wood legs, 72 by 44½ inches, $95.

Tantalus, rosewood, gilt, brass inlay, mother-of-pearl panels, shaped sides, flattened ball feet, $130.

Motorcycle license plate, Oklahoma, OKLA 915, red border, red text, cream, circa 1932, 8 by 4 inches, $180.

Tapestry, man in a garden holding a whip, dogs, fountain, portico, 1800s, 80 by 90 inches, $250.

Salesman sample, Aldek scaffolds, aluminum, configuration photos, briefcase, green handles, 19 by 18 inches, $340.

Coin operated skill machine, Major Novelty, marquee, wood case, yellow, red, 37 inches, $420.

Orange Crush door push, “Come in Drink,” bottle, straw, orange, black, 1920s, 12 by 3 inches, $660.

Capo-di-monte nativity scene, Greek columns, urns, arches, vines, flowers, 18 inches, $700.

Mills slot machine, 25 cent, castle front, shield, red, cobalt blue, wood case, $1,200.

Louis Vuitton Bellevue tote, purple patent leather, gold metal hardware, tan straps, 17 by 11 inches, $1,400.