Finally had to go look up a recipe for the Chinese eggs, which are made from Duck eggs.

[link to www.recipesource.com]

---------- Recipe via Meal-Master (tm) v8.02

Title: PRESERVED DUCK EGGS (THOUSAND YEAR OLD EGGS)
Categories: Eggs, Chinese
Yield: 12 servings

2 c Tea, very strong black
1/3 c Salt
2 c Ashes of pine wood
2 c Ashes of charcoal
2 c Fireplace ashes
1 c Lime*
12 Duck egg, fresh

*Available in garden stores and nurseries.

Combine tea, salt, ashes and lime. Using about 1/2 cup
per egg, thickly coat each egg completely with this
clay-like mixture. Line a large crock with garden soil
and carefully lay coated eggs on top. Cover with more
soil and place crock in a cool dark place. Allow to
cure for 100 days. To remove coating, scrape eggs and
rinse under running water to clean thoroughly. Crack
lightly and remove shells. The white of the egg will
appear a grayish, translucent color and have a
gelatinous texture. The yolk, when sliced, will be a
grayish-green color.

To serve, cut into wedges and serve with:

Sweet pickled scallions or any sweet pickled vegetable

Sauce of 2 tablespoons each vinegar, soy sauce and
rice wine and 1 tablespoon minced ginger root.

Preserved Ancient Eggs

These are often called thousand-year eggs, even
though the preserving process lasts only 100 days.
They may be purchased individually in Oriental markets.

The description of the whites turning grayish
isn't quite accurate from the ones I've seen. They're
more a dark blackish amber color-- quite attractive
actually.