QuestionA geology professor at Occidental College in California said that an easy test for hematite is as follows:
Take the stone in question and scratch it along the bottom of a china plate. If it is genuine, the mark left will be red. If it is fake, the mark will be gray.
Have you heard of this and do you agree with it?
Thanks for your time,
Jayne
AnswerJayne, other minerals may leave a red to reddish streak on porcelain surfaces. The key to using such a test is to eliminate other minerals by other characteristics such as appearance, surface luster, break edges, magnetic properties, hardness, etc.
Hematite does indeed leave a red streak on a porcelain streak plate. Some may use the back of a china plate, others the back of a porcelain tile or a purchased streak plate made for the purpose of field tests of minerals streak color.
I assume you will be able to eliminate plastics, etc., fairly easily without a streak test.
The fake hematite made from other minerals called Hematine should not leave the red streak. Hematite does streak red.
The porcelain streak will not work for minerals harder than the porcelain, such as quartz, because the material will scratch the test plate surface.
If stones are already set, it may be difficult to test without leaving a spot on the stone. If you can get to an unseen area, by all means use this streak test along with magnetism(hematite is not attracted to a magnet and the Hematine sort of fake is attracted).
Jayne, the professor makes a valid point. Go try it!
God Bless and Peace. Thomas. August 5,207 2:24pm
