Short answer: in today's trade, chrysanthemum stone is a dark, bitumen-rich limestone from southern China with white "flowers" of radiating celestine (strontium sulfate) intergrown with calcite. It is soft, around Mohs 3 throughout, and sold mostly as polished slabs and carvings. Because good natural flowers have become scarce, many pieces now have their dark background dyed, and some are plain limestone with no celestine at all. The flower should be crystal, not a gap left by paint.
Why does the name cover more than one rock?
"Flower stone" is a description, not a mineral name. The German gemological lab EPI, in its note on chrysanthemum stones, points out that rocks with radially grown andalusite, volcanic rocks with radially arranged feldspars, and limestones with bundles of celestine have all been compared to flowers. In Japan such stones are called "kikuka seki" or "kikka seki", roughly "chrysanthemum stone". EPI adds that there is no scientific definition of the term.
That is why buyers meet at least three different materials under one name:
| Trade name | Rock | Flower mineral | Typical source named |
|---|---|---|---|
| Chrysanthemum stone (Chinese) | Dark bitumen-rich limestone | Celestine with calcite | Hunan and Jiangxi, China |
| Flower porphyry | Andesite or rhyolite porphyry | White feldspar, often oligoclase | Greece, Australia |
| Japanese kikka seki | Various | Radiating crystals | Japan |
EPI recommends keeping "chrysanthemum stone" for the dark Chinese limestone with celestine and calling the volcanic material "flower porphyry". That is a sensible convention and the one this guide follows. The trade names guide covers why loose names like this cause so much trouble.
What is the Chinese chrysanthemum stone made of?
Two minerals in a black rock.
The matrix is limestone, which Geology.com defines as a sedimentary rock made mostly of calcium carbonate, CaCO3, that usually forms in clear, calm, warm, shallow marine water. The Chinese material is dark because it is rich in bitumen, which EPI describes as a black limestone rich in bitumen from Hunan province.
The petals are celestine (also spelled celestite), strontium sulfate, SrSO4, intergrown with calcite. Mindat's celestine data gives a hardness of 3 to 3½ and perfect cleavage, and calculates strontium as 47.7% of the mineral's weight. Minerals.net puts its specific gravity at 3.9 to 4.0, notes that it occurs in sedimentary rocks such as limestone, and calls it the most common strontium mineral and the element's primary ore. The celestite guide covers the blue crystal form most collectors know.
| Part | Mineral | Formula | Mohs | Specific gravity |
|---|---|---|---|---|
| Petals | Celestine | SrSO4 | 3 to 3.5 | 3.9 to 4.0 |
| Petals and matrix | Calcite | CaCO3 | 3 | 2.7 |
| Matrix | Limestone (mostly calcite) | CaCO3 plus organic matter | about 3 | varies |
Calcite figures are from Geology.com's calcite article. The upshot for a buyer: every part of this stone is soft. A steel knife scratches the flowers and the background alike.
Where does it come from, and how did the flowers grow?
EPI dates the Chinese material on the European market to the 1990s and names Hunan as the source, with a photographed specimen labeled from "Jianxi" (Jiangxi). The scientific reference EPI cites is a 1991 report by Fang Ye-sen and Yuan Xu-yin on chrysanthemum-shaped celestite in the Permian carbonates of the Pingxiang-Leping area in Jiangxi Province. Mindat's celestine locality list includes Yonghe in Liuyang City, Changsha, Hunan, credited to Yesen Fang in 1988, the same researcher behind the Jiangxi report.
Those references tell you the setting: Permian marine carbonate, roughly 250 to 300 million years old, deposited as limy mud. Strontium is a common trace element in seawater carbonates, and when it is concentrated and released as sediments compact and recrystallize, celestine can grow inside the rock. Crystals that start from one point and grow outward in every direction within the plane of a bed give the radiating, petal-like bundles. Treat this paragraph as the general picture of how sedimentary celestine forms rather than a measured history of any one quarry; the published work on these specific beds is not available in English online.
How is chrysanthemum stone faked or treated?
This is where EPI's work is most useful, because the lab actually tested pieces. Its account runs like this:
- Demand outran supply. Collectors wanted crisp white flowers on black. Natural flowers with good shape grew scarcer.
- Retouching began. The irregular celestine columns were given even outlines and "beautiful looking tips". Interestingly, EPI notes, it is not the white petals that get painted on: the surrounding limestone is colored black to sharpen the contrast.
- Complete imitations followed. Light gray limestone with no celestine is dyed black, leaving the flower shapes undyed, so that a painted negative of a flower appears.
- The lab check. Raman analyses carried out by EPI in 2013 on various Chinese chrysanthemum stones found celestine only in the uncolored specimens. The dyed pieces were always dyed limestone with no sign of celestine.
That last result is the one to remember. On EPI's sample, a dyed background meant no real flower.
Checks you can do before buying
- Petal texture. Real celestine petals are crystalline: under a loupe you see elongated blades with cleavage steps and a slightly glassy or pearly luster. A painted-around flower is the same dull, fine-grained limestone as the background, only paler.
- Edges. Natural petals have ragged, uneven terminations. Perfectly smooth outlines and uniformly pointed tips on every petal match EPI's description of retouching.
- Background color. Natural matrix is dark gray to black with some variation. An even, inky black that stops sharply at each petal suggests dye.
- Weight. Celestine is heavy for a light colored mineral, close to 4.0 in specific gravity against 2.7 for calcite. A piece with large flowers should feel slightly dense in the hand, though the effect is small in a mostly limestone carving.
- Description wording. Look for listings that name celestine or celestite. A listing that calls the piece quartz, or adds coated "aura" color, is describing something else or something altered, and is worth a direct question.
How should you care for it?
Everything in chrysanthemum stone is around hardness 3 and dissolves in acid. Geology.com notes that limestone effervesces in contact with a cold 5% hydrochloric acid solution, which is the identification test and also the warning: keep vinegar, citrus cleaners and descaling products away from it. Dust with a soft brush, wipe with a barely damp cloth and dry it. Celestine has perfect cleavage, so a knock can lift a flake from a petal. The International Gem Society notes that blue celestite may fade from heat or light; the white petals are less of a concern, but there is no benefit in sun exposure. Display slabs on padded stands and away from heaters.
What is it associated with in tradition?
In East Asian decorative tradition the chrysanthemum is a flower of autumn and long life, and that symbolism attached to the stone, which is why so much of it is cut as carvings, slabs and desk ornaments. In modern crystal traditions it is associated with growth and good fortune. These are cultural meanings, not properties of the rock.
What to look for when you buy chrysanthemum stone
Insist on knowing what the flowers are made of. The ideal piece shows several whole flowers with crystalline petals, an unforced dark matrix, and a description that names celestine. For carvings, check that the carver placed a flower on a visible face rather than cutting through it. Ask for a close-up photo of one petal under raking light.
- Chrysanthemum Stone Quartz Carving with Aura Inclusions: a single 2.26 lb (about 1,025 g) carving with radiating flower patterns; because the listing describes quartz and added aura color rather than celestine, ask for a petal close-up and treat it as a decorative carving.
- Celestite crystal cluster on matrix: a 2 x 1.5 x 1 inch, 51 g cluster; a free-grown look at the mineral that forms genuine petals, useful for learning its luster and cleavage.
- White celestite with golden calcite from Clay Center, Ohio: thumbnail specimens pairing celestine blades with calcite crystals, the same two minerals that make up the flowers, from a limestone quarry locality.
For carved pieces generally, see the carvings guide, and for Chinese localities, the China origin guide.
Digital Towns Market
Chrysanthemum stone in stock
Frequently asked questions
What is chrysanthemum stone made of?
The Chinese material sold under this name is dark, bitumen-rich limestone with white flowers of radiating celestine, strontium sulfate, intergrown with calcite. Volcanic rocks with flower-shaped feldspar crystals are sometimes sold under the same name but are better called flower porphyry.
Is chrysanthemum stone natural?
Untreated pieces are natural. EPI's 2013 Raman tests showed many dyed pieces contained no celestine at all: they were gray limestone dyed black around undyed flower shapes. Check that petals are crystalline and that the background is not an even, inky black.
Where does chrysanthemum stone come from?
The best known Chinese sources are in Hunan province, including the Liuyang area, and Jiangxi province, in Permian marine limestones. Japan has its own flower stones, called kikka seki, and flower porphyry comes from Greece and Australia.
How hard is chrysanthemum stone?
Soft. Celestine is 3 to 3.5 on the Mohs scale and calcite and limestone about 3, so a knife or even a harder stone in the same bag can scratch it. Keep it away from acids, which attack the limestone.
Is chrysanthemum stone the same as celestite?
Not exactly. The flowers are made of celestine, the same mineral as blue celestite crystals, but chrysanthemum stone is the whole rock: limestone matrix plus white celestine and calcite petals. Celestite crystal clusters are the free-grown form of the mineral.
Sources
- EPI Institute for Gemstone Testing, Chrysanthemum stone and flower porphyry: https://epigem.de/en-us/topics/chrysanthemum-stone.html
- Mindat, Celestine: https://www.mindat.org/min-927.html
- Minerals.net, Celestine: https://www.minerals.net/mineral/celestine.aspx
- International Gem Society, Celestite value, price and jewelry information: https://www.gemsociety.org/article/celestite-jewelry-and-gemstone-information/
- Geology.com, Limestone: https://geology.com/rocks/limestone.shtml
- Geology.com, Calcite: https://geology.com/minerals/calcite.shtml