Celestine, also known as celestite, is a strontium sulfate mineral belonging to the class of anhydrous sulfates. The mineral is known for its captivating sky-blue to colorless shades, as well as its orthorhombic crystal system, which forms tabular or prismatic crystals. Celestine can also occur in compact or fibrous masses, exhibiting a vitreous to pearly luster and a transparent to translucent appearance.


Celestine is primarily used as a source of strontium, an essential element in the production of various compounds, such as strontium carbonate, which is employed in the manufacturing of glass, ceramics, and pyrotechnic materials. Strontium is also used in the creation of specialized alloys and electronic components, as well as in the healthcare industry for the treatment of specific medical conditions.


Although not commonly considered a mainstream gemstone, celestine’s striking blue color and relative rarity can make it an appealing choice for collectors and enthusiasts seeking unique and eye-catching specimens. The mineral’s delicate crystal structure and cleavage, however, can make it challenging to work with and less suitable for everyday wear in jewelry items.


Celestine forms through various geological processes, including the precipitation of strontium-rich fluids in sedimentary environments, such as evaporite deposits or marine basins, and as a secondary mineral in hydrothermal veins or cavities in limestone and dolomite rocks. The mineral can also form as an alteration product of other strontium-bearing minerals in specific geological conditions.


Celestine can be found globally, with notable deposits in the United States, Mexico, Madagascar, and Poland. The mineral often occurs alongside gypsum, anhydrite, and halite in sedimentary rocks, as well as in cavities and geodes in limestone and dolomite formations. Its beautiful blue color and crystal habit make it a highly sought-after mineral among collectors.


In metaphysical and spiritual practices, celestine is believed to possess a calming and uplifting energy, fostering a sense of inner peace and serenity. The mineral is said to facilitate communication with higher realms and enhance spiritual growth, making it an ideal choice for meditation and energy work. Celestine is also thought to stimulate intuition, creativity, and clarity of mind, assisting individuals in overcoming obstacles and achieving their goals.

LusterVitreous to pearly
Hardness (Mohs)3 – 3.5
ColorColorless, white, pale blue, blue, yellow, orange, reddish-brown
CleavagePerfect in one direction, good in two other directions
Specific Gravity3.95 – 3.97