“Bloodspots” on Dzi beads («硃砂” in Chinese) are small red dots, often from the mineral cinnabar (mercuric sulfide) or iron oxides, that form during the bead’s creation.
Origin of the dots
Cinnabar: In the purest form, which is rare, the dots can be cinnabar (mercuric sulfide) from when mercury and sulfur were present during the agate’s formation.
Cinnabar dots occur when mercury and sulfur are present during the formation of agate. Mercuric sulfide, also known as cinnabar, is produced when mercury reacts with sulfur. In its purest form, cinnabar is a deep red color and is used to make vermilion pigment. However, it’s rare to find it in its purest form in agate, as other materials are usually present, resulting in slight variations in its redness.
Iron Oxides: More commonly, the spots are caused by ferric oxide (or iron oxides) resulting from the iron in the agate being exposed to air.
Brown spots that resemble rust are usually iron oxides or hydroxides, which are basically oxidized iron. Agate is often manipulated by the addition of iron oxides or hydroxides to create the appearance of bloodspots.
Why do most producers not use mercuric sulfide? There are two reasons for this: one, mercuric sulfide is highly toxic, and two, it’s more difficult to manipulate into artificially-made agate. Iron dust is a much easier alternative.
Many Dzi dealers try to pass off anything with speckles and dots as cinnabar dots because they fetch much higher prices. However, it’s important to note that not all speckles and dots are cinnabar dots. It can be challenging for collectors to differentiate between cinnabar dots and other types of speckles, but it’s crucial to do so to avoid buying counterfeits or overpriced beads.
Although, to be fair, it should be said that any “bloodspots” can look very beautiful.
I made several dZi beaded jewelry.These dZi beads have a lot of beautiful red dots🙂.
Photos by my website DzidZen