Assertion: porcelain's color | /r/HasProperty | achieved
Facets:
value: by using cobalt oxide
type: MANNER
value: by adding pigments
type: MANNER
Source sentences:
text: For now, just know that the colors and patterns on porcelain countertops are achieved by adding pigments (known as “glaze”) to the surface.
text: The blue color was achieved by using cobalt oxide, a technique developed during this time period.