By MICHAEL MORAIN REGISTER STAFF WRITER Adel, Ia. - Bob Andersen makes all kinds of beautiful stoneware in his pottery studio in Pella, but frankly, some of his most popular work is hideous. Contorted. Even repulsive. But intentional. On his handmade "ugly jugs," bulging clay eyeballs peer out beneath extravagantly messy eyebrows. Fleshy lips frame crooked teeth. Giant nostrils flare from jumbo-sized schnozzes. With their grotesque features - all wobbly lines and comic expressions - the jugs look like Quentin Blake's illustrations for Roald Dahl. (When asked if he modeled the jugs after anyone in particular, Andersen politely declined to name names.) Homely as they are, the jugs have become a popular tradition at the annual spring pottery show at Atherton House, a gift store in a quaint gray house a block away from Adel's courthouse square. Fans call ahead to ask about each new batch of jugs - once, they began asking Andersen about them even before he got out of his van. By the time he stepped inside the store, he'd sold the collection. Andersen is just one of more than 85 potters from about 30 states, including a dozen from Iowa, whose work will be on display today though Sunday, in tents crowded in the tulip gardens around Atherton House. The outdoor show, known as a kiln opening, follows a tradition popular in the hilly Piedmont and western mountain regions of North Carolina, an area famous for its handcrafted pottery. After a firing, potters open up the kiln and display their work on the ground, tables and tree stumps for immediate purchase by customers who may have waited in line for hours. In rural North Carolina, artists often post signs for kiln openings on bulletin boards in gas stations and grocery stores. "Every other mailbox has a pottery sign on it," said Miriam Dunlap, who owns Atherton House with her husband, David Larson, and has traveled throughout the country to recruit potters for the show. Since their first show eight years ago, when pottery from six artists lined a single bench out in the yard, the event has grown into a big deal for collectors and people who just want an excuse to get outside. More than 1,400 people visited last year's show, including several Californians who plan an annual vacation around the event. "It's like Art in the Park, but it's a madhouse," said Michelle Peacock of Urbandale, surprised by how many people line up early in the morning on the first day. "I was like, 'Wow, this is cool. I should have come earlier.'" Many people come to stock up on gifts for holidays and birthdays, and Dunlap said a number of customers have told her they prefer to buy wedding presents here rather than via a computerized registry at a chain store. Of course, some customers couldn't care less about the pottery. The minute they step inside the gate, they ask about the Derby Pie. The Southern pecan pie - made with chocolate chips, vanilla and a splash of bourbon - is a 12-year tradition at Atherton House and will be a tasty, calorie-charged part of this year's event. And it's free! "I have 1,100 pieces in the freezer as we speak," Dunlap said earlier this week. Reporter Michael Morain can be reached at (515) 286-2559 or email@example.com FORM AND TEXTURE Potters shape most pieces by hand or with the aid of an electric or foot-pedaled wheel. Once they've made the basic form, many potters add textures by imprinting the moist clay with a range of tools. Bob Andersen embellished a series of stoneware with all kinds of odds and ends: A bike gear from a scrap bin at Michael's Cyclery in Ames. A broken Japanese paintbrush. Andersen made clay stamps for the leaf and spiral designs. The edge of a seashell. The tread from a 1970s-era Adidas running shoe. POTTERY 101 CLAY TYPES Pottery comes in all colors, shapes and sizes, but most work fits into one of three categories: · Earthenware and terra cotta is made with slightly porous, usually reddish clay and fired at a temperature cooler than 2,000 degrees Fahrenheit. · Stoneware is made with brownish clay and fired at a temperature between 2,000 and 2,400 degrees Fahrenheit. · Porcelain is made with pure white clay and fired at a temperature between 2,000 and about 2,600 degrees Fahrenheit. "THUNK" TEST To help determine what kind of pottery is which, pick up a bowl or a plate and flick it with your finger. If there's a dull "thunk" sound, it was probably fired at a temperature below 2,000 degrees Fahrenheit. If there's a resonant ping, the kiln was probably hotter. And if there's no sound at all, the piece may be broken. Check for hidden cracks. GLAZES To achieve certain glazing effects, potters often use detailed recipes because even slight variations in the chemicals or kiln temperature can cause dramatically different results. Adding salt to the kiln, for example, can add a glassy orange finish to the pottery. Adding wood ash can create a rustic, natural look.