Rare, unusual, well-made, historic - all of those things add to the monetary value of an antique. They also add to the "enjoyment factor" for an owner who wants to understand history and beauty. Two very unusual and important 19th-century whalebone chairs were sold in November at a Bonhams' auction in Sydney, Australia.

Few of us realize the importance of whaling in America and elsewhere in the 18th and early-19th centuries. Whales were plentiful. The Dutch, English, Spanish and Americans all had fleets of ships sent to bring back whale products. The whale was harpooned from a small boat, dragged back to the large ship, then skinned and butchered. The blubber was boiled to make whale oil, the preferred fuel of the day. It was used for lighting

The best whale oil came from sperm whales. The waxy oil in their heads was used to make candles that were smokeless and odorless. It was also a prime lubricant for machinery. Nothing else was as good until the 1860s, when oil was discovered in the ground.

Whalers lived a dangerous life, with exciting hunts leading to long days searching for more whales. During boring weeks, sailors carved whalebones and teeth into what is now called scrimshaw. All old scrimshaw is valuable, even corset busks, pie crimpers, letter openers, tools and other small pieces. All sell today for hundreds to thousands of dollars.

The chairs may be unique, and probably are the only full-size whalebone chairs known. They created great interest; one sold for $56,742 and the other sold for $49,832.

Q: I like to dig for old bottles, and just found two identical blown-glass bottles in a town in Illinois. The bottles are 6 5/16 inches tall, and appear to have had cork stoppers. The words embossed on them are, "Lynn's Medicines are Good."

A: Your bottles originally held a 19th-century "patent medicine" concoction advertised as a treatment for diarrhea. Patent medicines were promoted all over the United States from the mid-1800s into the early 1900s. The extravagant, and usually false, claims manufacturers made for many of these medicines was part of the reason Congress passed the Pure Food and Drugs Act in 1906. Your bottles are rare and are worth $300 to $400 each in good condition.

Q: I have a French ceramic coffee set for eight. The bottom is incised "Marius Giuge, Vallauris, France." I can't find any information about this maker.

A: Marius Giuge (1909-1980) was a potter who began working in Vallauris, a small town in Southern France, around 1950. Vallauris has been a pottery center since Roman times, and was known for its cookware. The industry began to decline in the early 20th century, after aluminum and plastic cookware became popular, but revived after Pablo Picasso began designing pottery in Vallauris in 1946. This attracted other potters as well as buyers, and many studios, shops and galleries opened up in Vallauris. There are now more than 200 potters working in Vallauris.

Q: I have been searching for information about a Hopalong Cassidy glass I own. It is milk glass with black and red decorations, and says "Snack Milk." I have been told the glass is rare and could be worth more than $1,000. Can you help me with more information?

A: Your Hopalong Cassidy tumbler was part of a boxed set of four milk glass tumblers to be used for breakfast, lunch, dinner and snacks. They were made with solid-black or black and red graphics. There is also a blue set. Each glass has different pictures. The "snack milk" glass features an image of Hoppy on one side and a verse on the other: "Hoppy says: 'Milk with snacks will help you hustle, builds strong bones 'n teeth 'n muscle.'" The snack glass is the hardest to find, especially the solid-black version. Individual tumblers from this set are selling for $40 to $60. The snack tumblers sell for $100 to $295. The one with the solid black decoration is at the higher end. Complete sets with the original box could sell for as much as $600.

Q: Thirty years ago, I was given a large cast-iron Uncle Sam doorstop. Uncle Sam's lifted right arm is holding a star, and his left hand carries an American flag on a pole. The figure is marked "Midwest Importers." When I had a garage sale a while back, a man saw it and told me not to sell it because it could be valuable. What do you think?

A: Your doorstop was made in Asia, probably Taiwan, and was new or close to new when it was given to you. The mark is the clue. Uncle Sam was imported and sold here by Midwest Importers. If in good condition, you might get $50 for it. The doorstops collectors hunt for are older ones made in the United States during the 1920s, '30s and '40s. Some sell for prices into the thousands.

Tip: To dry a small-necked bottle, give it a last rinse with alcohol.

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