Search: 637 results found for "scolecite"

Triple Stalactite Malachite | 6.5cm | DRC

(0)

£55.00

Sphalerite | 95mm | Picos de Europa, Santander, Spain

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£175.00

Permineralized Wood with Marcasite 37.1g

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£75.00

Cobaltoan Calcite with Malachite | DRC

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£51.00

Grey & White Calcite with Stilbite | Display Specimen | 200mm | China Minerals Tali & Loz Crystals

Grey & White Calcite with Stibnite | Display Specimen | 200mm | China

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£110.00

Crystallised Malachite Specimen | 10.4cm | DRC

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£75.00

Description Cards S-Z

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£1.50

Shattuckite Specimen | 235g | Kaokoveld Plateau, Namibia

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£55.00

Shattuckite Specimen | 217g | Kaokoveld Plateau, Namibia

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£55.00

Malachite Stalactite | 18cm | Democratic Republic of Congo

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£300.00

Charoite Cabochon 7gr

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£32.00

Sugilite Rough Mineral | 3.44gr | South Africa

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£69.00

Cobalto Calcite Rough 561g

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~~£85.00~~ £42.50

Malachite Stalactite Specimen 203gr, Zaire- Congo Minerals Tali & Loz Crystals

Malachite Stalactite Specimen | 203g | Zaire-Congo

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£52.00

Malachite Stalactite 36gr , Zaire- Congo Minerals Tali & Loz Crystals

Malachite Stalactite | 36g | Zaire-Congo

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£35.00

Malachite Stalactite 52gr | Zaire- Congo Minerals Tali & Loz Crystals

Malachite Stalactite | 52g | Zaire-Congo

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£35.00

Sphalerite with Minor Smithsonite on White Quartz | Nenthead

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£125.00

Barite on Malachite | 52mm | Shangulowe Mine, DR Congo

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£350.00

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Zeolite: Not One Mineral but a Family, and Why That Makes It Even More Interesting

What is Zeolite? Mineral Group: Tectosilicate | Category: Zeolite Group | Formula: Variable | Hardness: 3.5 – 5 (Mohs) Zeolite is not a single mineral but a family of related hydrated aluminosilicate minerals that share a distinctive open framework crystal structure and a common mode of formation in volcanic environments. The group includes dozens of recognised species, among them Stilbite, Heulandite, Scolecite, Analcime, Chabazite, Natrolite, and Thomsonite, each with its own specific chemistry, crystal habit, and physical properties, but all united by the same fundamental architectural principle: a three-dimensional lattice of silicon, aluminium, and oxygen that contains interconnected channels and cavities large enough to accommodate water molecules and exchangeable ions. The name Zeolite was coined in 1756 by the Swedish mineralogist Axel Fredrik Cronstedt, who observed that certain minerals frothed and appeared to boil when heated rapidly. He combined the Greek words zein, meaning to boil, and lithos, meaning stone, to produce the term. The boiling behaviour he observed results from the rapid expulsion of structural water trapped within the crystal framework as heat drives it out, a property that reflects the open, porous nature of the zeolite structure and remains one of the group's most characteristic features. Formation and Geological Context Zeolites form as secondary minerals, meaning they develop not during the primary crystallisation of a rock but through later chemical processes acting on existing volcanic material. The most common setting is within the cavities, vesicles, and fractures of basaltic and andesitic volcanic rocks, where silica-rich hydrothermal fluids circulate at relatively low temperatures, typically between 50 and 300 degrees Celsius. The process begins when volcanic rock, particularly basalt or volcanic ash and tuff, is buried and comes into contact with groundwater. The water dissolves silica, aluminium, and various cations from the surrounding rock and carries them in solution through the available void spaces. As these fluids cool, or as their chemistry changes through reaction with the host rock, the dissolved components begin to crystallise onto the cavity walls. Given sufficient time and stable conditions, well-formed crystals grow inward from the walls of the cavity, producing the characteristic drusy clusters that make Zeolite specimens so visually appealing. The temperature and pressure conditions of formation, along with the precise chemistry of the circulating fluid and the host rock, determine which specific Zeolite species crystallises. This is why different Zeolite species tend to be associated with different geological environments and depths within a volcanic sequence. Zeolites forming deeper in a sequence, where temperatures are higher, tend to differ systematically from those forming closer to the surface. Geologists use the distribution of Zeolite species through volcanic sequences as a tool for reconstructing the thermal history of the rock. Major producing regions include the Deccan Traps of India, one of the largest volcanic provinces on Earth, which has yielded some of the world's finest and most diverse Zeolite specimens. Iceland, where active and recently active volcanism provides ideal formation conditions, is another significant source. The western United States, parts of Eastern Europe, and various localities across Brazil and New Zealand also produce notable material. Indian Zeolite specimens are particularly celebrated among collectors for the scale and quality of their crystal formations, frequently occurring in large basalt cavities alongside Apophyllite, Calcite, and Chalcedony in combinations that are among the most visually spectacular in mineralogy. Key Physical Properties Property Detail Mineral Group Tectosilicate Category Zeolite Group Crystal System Variable by species Hardness 3.5 – 5 Mohs Specific Gravity 2.0 – 2.4 (variable) Refractive Index Variable by species Lustre Vitreous to pearly Fracture Uneven Cleavage Perfect to good depending on species Tenacity Brittle Transparency Transparent to translucent Colour Colourless, white, cream, peach, pink, green Formula Variable (hydrated aluminosilicates) Safe to Cleanse in Water Brief contact tolerated; prolonged soaking not recommended The variable physical properties across the group reflect the structural and chemical diversity of the individual species. Specific gravity tends to be low across all Zeolites relative to other silicate minerals, a direct consequence of the open framework structure that contains significant void space within the crystal lattice. This porosity, which is what makes Zeolites so scientifically and industrially significant, also makes them less dense than most minerals of comparable chemistry. The Open Framework Structure The defining characteristic of all Zeolites, the feature that unifies the group and explains both their geological behaviour and their industrial importance, is the open framework structure. Understanding it helps make sense of almost everything else about these minerals. In most silicate minerals, silicon and oxygen atoms form compact, densely packed arrangements that leave little internal space. In Zeolites, the silicon and oxygen framework is built around a three-dimensional network of interconnected rings and channels, creating a structure that is more like a microscopic sponge or a molecular cage than a solid lattice. Aluminium substitutes for silicon at various points in the framework, and the resulting charge imbalance is compensated by cations such as sodium, potassium, calcium, or magnesium occupying positions within the channels. Water molecules also occupy these channels, held loosely within the structure by electrostatic attraction rather than by strong chemical bonds. This is why Zeolites can be dehydrated by heating without the crystal structure collapsing, and why they can reabsorb water from the surrounding environment when cooled. The channels are large enough for water molecules and small ions to pass through freely, which is the basis for the ion exchange and molecular sieving properties that make Zeolites so valuable industrially. The specific geometry of the channels varies between species and determines which molecules or ions can enter and which cannot, essentially acting as a molecular size filter. This precise selectivity is what makes different Zeolite species useful for different industrial applications, from water softening to catalytic cracking in petroleum refining. Principal Collector Species While the Zeolite group contains over 40 naturally occurring species, a handful account for the vast majority of collector specimens and are worth knowing individually. Stilbite is one of the most widely collected Zeolites, recognised by its characteristic sheaf-like or bow-tie crystal aggregates. It typically occurs in white, cream, peach, or pale salmon tones and forms some of the most elegant natural crystal arrangements available to collectors. Fine Stilbite specimens from the Deccan Traps of India are benchmarks of the group. Heulandite forms flattened, coffin-shaped crystals, a habit distinctive enough to make identification straightforward even without chemical analysis. It occurs in a range of colours including colourless, white, yellow, orange, and green, the latter coloured by trace amounts of nickel. Large transparent Heulandite crystals from Iceland are among the finest in the group. Scolecite forms slender, acicular crystals that often grow in radiating or divergent sprays. It is typically colourless to white and has a particularly silky lustre on crystal surfaces. Scolecite from Nashik in India has produced some of the most spectacular radiating crystal clusters known from the group. Analcime forms well-developed trapezohedron crystals, a form with 24 triangular faces that gives it a rounded, almost spherical appearance. It is typically colourless to white and is one of the more common Zeolites in basaltic rocks worldwide. Natrolite forms needle-like prismatic crystals with a characteristic square cross-section and perfectly smooth faces. It is typically colourless to white with a bright vitreous lustre and is found in many of the same basaltic localities as other Zeolite species. Zeolites in Industry and Science The industrial significance of Zeolites extends far beyond their importance to mineral collectors and is worth understanding as context for what makes the group structurally unusual. Natural Zeolites have been used for centuries in construction materials, water purification, and agriculture. Synthetic Zeolites, engineered to have specific channel geometries and chemical properties, are now produced in vast quantities and are among the most commercially important materials in modern chemistry. The global synthetic Zeolite market is measured in millions of tonnes annually. In petroleum refining, Zeolites serve as catalysts in the fluid catalytic cracking process that converts heavy crude oil fractions into more useful lighter products including petrol. In detergents, they replace phosphates as water softeners by exchanging calcium and magnesium ions for sodium. In gas separation and purification, their molecular sieving properties allow specific molecules to be selectively absorbed or excluded. In medicine, Zeolites are being investigated for drug delivery, wound treatment, and dialysis applications. The natural specimens in a mineral collection are a window into the same structural principles that underpin all of these applications, formed not in a chemical plant but over thousands of years within a basalt cavity. Mineral Associations One of the features that makes Zeolite specimens particularly appealing to collectors is the richness of their mineral associations. Because they form as part of a broader secondary mineralisation event within volcanic cavities, Zeolites are frequently found alongside other minerals that crystallised from the same hydrothermal fluids under similar conditions. Apophyllite is perhaps the most celebrated associate, and the combination of Apophyllite and Stilbite or Scolecite on a single basalt matrix piece from India represents one of the most recognisable and sought after combinations in the collector market. Calcite occurs widely alongside Zeolites in many localities. Chalcedony, a fine-grained silica mineral, often lines cavity walls as a precursor to Zeolite formation or fills remaining void space. Prehnite, Pectolite, and various other secondary silicates are also common associates depending on locality. Care and Handling Zeolites contain structural water as part of their crystal framework and are consequently sensitive to conditions that affect their hydration state. Rapid heating or exposure to very dry environments can cause dehydration stress, potentially resulting in surface dulling, micro-fracturing, or in extreme cases structural damage. Brief contact with water is generally tolerated by most Zeolite species, but prolonged soaking is not recommended. The combination of relatively low hardness (ranging from 3.5 to 5 on the Mohs scale) and brittle tenacity means that Zeolite crystals, particularly the fine acicular habits of species like Natrolite and Scolecite, are vulnerable to mechanical damage. Handle specimens with care and support the matrix rather than gripping individual crystals. Store in stable indoor conditions away from heat sources, direct sunlight, and significant humidity fluctuations. Clean with a soft dry brush. Avoid ultrasonic cleaning equipment, which can shatter delicate crystal aggregates, and any liquid-based cleaning methods that involve prolonged contact. Traditional Associations While this guide focuses on the science of Zeolites, individual species within the group are valued in spiritual and mindful practices for a range of associations connected to their specific colours, habits, and energies. These associations are rooted in cultural and traditional use rather than scientific properties. For explorations of individual Zeolite species in spiritual practice, see our dedicated guides to Stilbite and Scolecite. Summary Zeolite is one of the most structurally distinctive and scientifically significant mineral groups available to collectors. Formed through low temperature hydrothermal processes within volcanic cavities, the individual species that make up the group offer a remarkable diversity of crystal habits, colours, and associations within a shared architectural framework. The same open channel structure that makes natural Zeolite specimens so visually compelling is the basis for one of the most industrially important classes of materials in modern chemistry. Whether encountered as a delicate spray of Scolecite needles, a peach-toned Stilbite sheaf, or a glassy Heulandite crystal, every Zeolite specimen is a record of slow, patient crystallisation from hydrothermal fluids within ancient volcanic rock. Shop all Zeolite As always, our inbox and DMs are open if you would like guidance or simply wish to explore further. Contact us Love, Laura Further Reading Stilbite: The Zeolite That Looks Like a Bow Tie Scolecite: The Silky Zeolite From the Heart of a Volcano Apophyllite: The Glassy Mineral That Grows Alongside Zeolites Clear Quartz: The Mineral Inside Your Watch, Your Phone, and Your Collection Black Tourmaline: The Mineral That Generates Its Own Electricity Everything you Need to Know about Quality Of Crystals Zeolite Family Mineral Guides

on Apr 16 2025

Blog

Unlocking the Transformative Power of Crystals for Teens

Crystals for Teens For centuries, the allure of crystals has enchanted humanity from all walks of life. These precious gems hold within them the potential to elevate our lives, and today, we delve into the realm of crystals that resonate particularly with teenagers. In the midst of the whirlwind of growth and self-discovery, crystals stand as steadfast allies, offering calmness, clarity, and positive energy. Whether seeking to alleviate stress, enhance focus, or cultivate an overall sense of well-being, the following crystals are great to accompany teens on their journey of self-exploration. Rose Quartz: Embracing Self-Love The tender embrace of Rose Quartz is a beacon of love and compassion. Its delicate pink hues foster a deep sense of tenderness, nudging teens towards self-love and acceptance. As it gives warm energy, healthy relationships bloom and emotional healing takes root. Petroleum Quartz: Igniting Inner Resilience Gaze upon the wonders of Petroleum Quartz, a crystal resembling an artist's masterpiece, an ode to strength and fortitude. This gem emanates an empowering aura, encouraging teens to conquer obstacles and embrace their untapped potential. With this crystal in tow, a surge of confidence and courage infuses every facet of their lives. Amethyst: A Path to Intuition Amethyst is a majestic crystal suffused with regal purple hues that helps with self-discovery. By awakening the Third Eye Chakra, it amplifies intuition and spiritual awareness, guiding teens through life's labyrinth with unwavering trust in their instincts. Caribbean Calcite: A Dive into Serenity Imagine the serenity of a tropical paradise, encapsulated within the tranquil energy of Caribbean Calcite. Like the gentle lapping of crystal-clear waters, this gem soothes the mind and nurtures the soul, banishing stress and anxiety. By harnessing its serene vibrations, teens can create a haven of calm and tranquility wherever they go. Tiger's Eye: Unleashing Inner Confidence Evoke the spirit of the tiger with the mesmerizing tiger's eye, its golden bands reminiscent of the majestic feline's coat. This stone channels courage and confidence, shattering self-doubt and empowering teens to embrace their uniqueness. Something Different As conduits of transformation, crystals hold the power to reshape our lives, an enchanting symphony of energy and intention. For teens navigating the labyrinth path of adolescence, these remarkable gems stand ready to support, uplift and inspire. These are some out of the box thinking crystals that suits teens very well! Astrophyllite: Illuminating Inner Journeys With Astrophyllite, teens embark on celestial journeys of self-discovery. Like stars scattered across the night sky, this crystal illuminates their path, guiding them towards inner revelations and heightened awareness. Its energies foster a deep connection between the physical and spiritual realms, bridging the gap between Earth and the cosmos. Apophyllite: Awakening the Spirit Apophyllite's ethereal beauty conceals profound energies, boosting teens to connect with their higher selves. Its radiant presence uplifts the spirit, clearing the mind of clutter and inviting tranquility. This crystal serves as a portal to spiritual growth, aiding teens in their pursuit of enlightenment and self-realization. Nuummite: Embracing the Shadows Nuummite, with its mysterious allure, invites teens to delve into the depths of their subconscious. It acts as a mirror, reflecting hidden truths and unresolved emotions. By embracing their shadows, teens can pave the way for profound healing and transformation, emerging stronger and wiser. Lodalite: A Glimpse into Infinite Realms Lodalite, often referred to as the "shamanic dreamstone," unveils a world of infinite possibilities to curious teens. Within its mesmerizing inclusions lies a tapestry of ancient wisdom and cosmic insights. As they gaze into its depths, Lodalite encourages introspection and exploration of alternate dimensions. Scolecite: Elevating Spiritual Awareness Scolecite's delicate energy resonates harmoniously with teens seeking to deepen their spiritual connection. Like a gentle breeze, it sweeps away mental clutter and paves the way for inner clarity. By facilitating communication with higher realms, Scolecite encourages teens to embrace their innate wisdom. Incorporating these crystals into the lives of teens is an act of empowerment and enrichment. Whether nestled in pockets, adorning jewellery or placed in personal spaces, these gems serve as steadfast companions for self-discovery. Remember, within every crystal lies a universe of possibilities, and within every teenager lies the potential to unearth their true brilliance. If you are not sure about which crystal is best suited to you, feel free to reach out to us and we can help you in making a conscious choice about the best-suited crystals. Contact us here Love & Light, Laura Related Blog Posts Want to learn more about how to work with crystals and minerals? Check out our other Guides: Best Crystals for Confidence Amber: The Golden Whisperer of Timeless Wisdom and Protection Best Crystals for Introverts & How to use them Charoite: A Journey of Transformation and Spiritual Growth Crystals and Sacred Geometry Crystals Grids 101 Advanced Crystal Choosing How to Choose the Right Crystals Based on Their Shapes Selenite: The Stone of Higher Consciousness

on Jan 13 2025

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