Posted 12 months ago
Vron121
(38 items)
Hi does anybody know what this mirror is ebony or plastic age? Mirror has deteriorated a little bit, might be the age, have looked at all the mirrors I can find, it’s a nice shape mirror. Size length 11” x 7” 1/2”
"New glass is thinner and gives a whiter reflection than old glass. You can test this by holding the edge of a white card against the glass. If the card and the reflection are the same white color, the mirror was made after 1850. If the reflection is more yellow or gray, the glass was made before 1850."
Both natural (tortoise shell and horn) and synthetic (celluloid) are glowing under black light.
"Virtually all plastics and resins fluoresce blue or blue/white under long wave black light regardless of the surface color in ordinary light. Genuine ivory usually fluoresces white but this can vary depending on whether the ivory has a patina. Most natural old patinas fluoresce dull yellow or brown. Be very suspicious of any brightly colored fluorescence such as yellow as this indicates artificial aging in dung, urine or animal fats. Use black light as your first test, not your only test. Black light is useful for eliminating artificial materials but can not alone prove a piece is ivory. Bone, vegetable ivory (cellulose) and glued together ivory dust, for example, all react like genuine ivory under black light."