Explanation: If the color must be exact, my suggestion is that you contact the client and ask them.
While it is easy to figure out exactly what color they are refering to when they are refering to with marron glacé, the literal translation of "frosted chestnut brown" brings up hair color references instead of clothing related ones. The phrase "light chestnut brown" brings up links about horses, not clothing. Since the links to cars and clothing of "marron glacé" that I looked at appear to be a greyed brown, I suggest taupe or mushroom, but the client may have very specific needs as to why they have chosen their color name so, depending on your context, I would consider asking them.
marron; marron glacé [ma-ROHN glah-SAY]
Marron is the French word for "CHESTNUT." Marrons glacés are chestnuts that have been preserved in a sweet syrup. They can be found in jars or cans in the gourmet section of most supermarkets and are quite expensive. They're eaten as a confection, chopped and used to top desserts such as ice cream and mixed fruit or used to make desserts such as the rich MONT BLANC. http://www.epicurious.com/cooking/how_to/food_dictionary/ent...
Chocolatier Regis: truffe au chocolat, marrons glaces, vente en ligne de confi
Les marrons glacés http://www.chocolats.net/pages/marron.php
Chocolatier Regis: The finest hand-made chocolates, truffles, marrons glaces and sweets from Paris
The Marrons Glacés [This site doesn't translate the term.] http://www.chocolats.net/EN/index.php
-------------------------------------------------- Note added at 19 hrs 27 mins (2005-09-28 15:06:25 GMT) --------------------------------------------------
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I realize that I am bucking the trend here but "frosted chestnut brown" only gets two hits on Yahoo for human hair pieces. Without the quotation marks, the primary hits are still for wigs and hair dyes.
I've included two more references to show that a car referred to as "marron glacé" in France has been referred to as "champagne" in the U.S.