Same as porcelanous.

adjective. Of or relating to porcelain; resembling porcelain.

adjective. Having a smooth, compact shell without pores; said of certain Foraminifera.

"The commonest of the giant clams TRIDACNA GIGAS sometimes betrays evidence of past internal trouble by the presence of a concretion of porcelain whiteness and of porcellaneous texture, but such are not to be described as pearls and to be prized as rarities only."