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    • Crystal Growing STEM Thames & Kosmos
    • Crystal Growing STEM Thames & Kosmos
    • Crystal Growing STEM Thames & Kosmos
    • Crystal Growing STEM Thames & Kosmos
    • Crystal Growing STEM Thames & Kosmos

    Crystal Growing

    • STEM
    • Crystals & Materials
    • Age 10+

    Grow dozens of crystals across fifteen guided experiments.

    $29.95

    Grow dozens of dazzling crystals with this classic science kit! Experiment with four chemically different crystal types — octahedron-forming potassium alum, rapidly growing sodium sulfate, needle-shaped sodium acetate, and gypsum-based plaster. Mold plaster shapes like stars and pyramids, then grow colorful crystal layers or your own geode. Measure how crystallization affects solution temperature across 15 guided experiments in this best-selling kit — over one million units sold.

    Inside the manual

    Additional Info

    • Developed by educators and scientists
    • Step-by-step build instructions
    • Engaging illustrations throughout
    Download Manual

    What's in the Box

    • Piece Count: 25
    • 32 page manual

    Deeper Dive

    Grow dozens of dazzling crystals and conduct 15 illuminating experiments with this classic science kit. Experiment with four chemically different crystals each with different properties, including potassium alum crystals that form regular octahedrons, rapidly growing sodium sulfate crystals, long needle-shaped sodium acetate crystals, and plaster which is made from gypsum crystals.

    Mold fun plaster shapes, including stars, lightning bolts, dolphins, and pyramids, and grow layers of crystals on them. Use dyes to form colored crystals, and mix the dyes to grow a rainbow of custom colored crystals. Display your crystal creations in a clear treasure chest with a locking lid. Mold your own geode — a hollow rock with crystals growing inside — and create a beautiful crystal cavern inside.

    Experiment with growing crystals rapidly and slowly, and observe how that affects the crystal structures. See if you can grow one giant crystal, and many small crystals on the surface of a rock.

    Measure how the crystallization of solids out of a solution, and the dissolution of crystals back into solution, affect the temperature of the solution. Learn about the energy of crystallization. Investigate solutions, crystallization, and the chemistry of crystal growing. Learn about the structures and geometries of different crystal shapes.

    This kit is thoroughly tested and safe: Over one million units of this kit have sold worldwide. A full-color, 32-page experiment manual guides your experiments in crystal chemistry and Earth science.

    Ages

    10+

    Experiments

    15

    Piece Count

    25

    Manual Pages

    32 Pages

    Product Dimensions

    14.6 x 11.5 x 3.1 in.

    Product Weight

    2.3 lbs

    Manual Dimensions

    8.3 x 11.7 in.

    Batteries Required

    N/A

    Country of Origin

    Germany

    Year Released

    2023

    Reviews

    Straight from real parents

    We envision a world where everyone loves to learn.

    Our products inspire kids and families to think deeper, play longer, and figure stuff out. 

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      Everyone's a Scientist

      We turn complex science and technology into fun, hands-on experiences for kids and families. From crystal growing to advanced robotics, we make the challenging feel approachable and the approachable feel exciting.