Stone Cold

Great news for engineers who've spent the last 10 years painstakingly cutting vehicle weight: the hottest new interior trim material is . . . GRANITE!

Actually, officials at Mercedes-Benz familiar with the special-order granite trim package on the new top-line 2000 CL Coupe say the stone accents actually are very thin and don't weigh much more than the wood trim typically used. The granite layer is bonded to an aluminum backing just like wood.

The new Mercedes coupe is expected to debut in the U.S. this spring with a sticker in the $80,000 to $90,000 range (not including the extra cost of the Designo granite package), so don't expect similar genuine stone accents to show up on a Chrysler Concord or Ford Taurus anytime soon. But designers say faux stone and granite made from - what else? plastic - are going to be here almost as quick as you can say fake wood trim.

Until recently automotive designers pretty much had three choices when it came to decorative trim for interiors: real wood, fake wood, or just plain painted plastic. That left little room to create a unique personality for a specific type of car or truck. Typically a genuinely expensive vehicle priced at more than $30,000 or $40,000 would get real wood trim, a less pricey model would get the fake wood, or just plastic.

But designers and consumers complain that often even real wood is so heavily coated with special protective finishes that it doesn't look any better than the fake stuff. Privately, many automaker executives admit the only reason real wood is ever used is so they can say so in advertising.

But this rather careless attitude is changing as automotive design shifts to a new era that tries to lend a hand-crafted look to mass-produced interiors. One of the best current examples of this new aesthetic is the interior of the Audi TT Coupe, which is riddled with numerous metallic bits, bezels and accents. Another is the Porsche Boxster, which features finely honed brushed aluminum door handles on the interior.

Jeffrey A. Rose, vice president of technology at Textron Automotive Co., says these are examples of a new "industrial" design trend being championed by German automakers, particularly Volkswagen AG (which owns Audi). It features not only brushed metal and chrome accents but also very man-made-looking golf ball-type dimples and knurled textures on surfaces such as instrument panel covers. The industrial look is aimed at younger consumers and sporty vehicles, from the VW New Beetle to some upcoming sport/utility vehicles.

Not far behind, Mr. Rose says, will be rock-like mineral accents that will be aimed at older consumers and giving SUVs a macho, yet luxurious looking interior. Much of this trend is being driven by fashion trends outside automotive, Mr. Rose says. Granite and other types of stone are popular materials for countertops and other surfaces in the kitchens and bathrooms of luxury homes, so it seems only natural they would gravitate to luxury vehicles.

Mr. Rose says he's now getting requests from automakers to apply some of these same luxury designs to everyday cars in the $20,000 range. The key to the success of these new designs and materials, Mr. Rose says, is what he calls "authenticity."

In tomorrow's vehicles, he emphasizes interior materials will have to do more than just look like the real thing, they will have to feel like it as well. That means being smooth, solid and cool to the touch like real stone or metal. That's not easy, but some relatively inexpensive synthetic materials (read plastic) can come close.

Corian, a DuPont mineral-like plastic currently used for kitchen countertops has a "solid, depthy feel," that approximates stone, Mr. Rose says, without being nearly as heavy or costly.

"When it's mounted on a surface, you can't tell how much it weighs," adds Larry Cole, executive product planning manager at DuPont Automotive. It's relaxing and cool to the touch, making it ideal for knobs, handles, bezels and accent points, he says.

Mr. Cole also is trying to convince automakers to try a variety of other alternative materials to give interiors a new look, from Surlyn, which is shiny, highly reflective (it's used for golf ball covers) and can even be made translucent, to brownish, techy looking Kevlar composite. How much any of this will catch on remains to be seen, but one thing is certain: Interior designers will have a lot more choices than real wood, fake wood and painted plastic in the future.