I’m trying to teach a young child about different types of materials found on a beach. We’ve talked about sand, and now I want to get them thinking about what isn’t sand. I want something that prompts them to think about the composition and appearance of sand itself. Specifically, what are some common things you might find on a beach or in a sandy environment that, based on their material composition, texture, size, origin, or any other distinguishing factor, you wouldn’t classify as sand? Can you provide a range of examples, from the very obvious to the slightly less obvious, to really challenge their understanding?
Answer
Sand is defined by its grain size, typically ranging from 0.0625 to 2 millimeters in diameter. Therefore, anything outside that size range or not primarily composed of mineral or rock fragments is not sand. Here’s a more detailed breakdown:
Substances too small to be sand (smaller than 0.0625 mm):
- Silt: Finer than sand, with a particle size between 0.004 and 0.0625 millimeters.
- Clay: Even finer than silt, with particle sizes less than 0.004 millimeters. Clay particles are often plate-shaped.
- Mud: A mixture of silt and clay, often found in bodies of water.
- Dust: Fine particles, often airborne, composed of various materials (soil, pollen, pollutants).
- Dissolved minerals: Minerals broken down into ionic form and present within water.
Substances too large to be sand (larger than 2 mm):
- Gravel: Larger rock fragments ranging from 2 to 64 millimeters in diameter.
- Pebbles: Rounded stones, typically smaller than cobbles, often found on beaches and in riverbeds.
- Cobbles: Larger rounded stones, typically ranging from 64 to 256 millimeters in diameter.
- Boulders: Very large rocks, greater than 256 millimeters in diameter.
- Shells: Whole or large fragments of seashells.
- Coral: Whole or large pieces of coral skeletons.
- Seaweed: Marine algae.
- Plastic: Manufactured polymers, whether in large pieces or microplastics.
- Wood: Pieces of trees, branches, or manufactured wood products.
- Glass: Fragments of broken glass.
- Metal: Pieces of metal, such as scrap or debris.
Substances not primarily mineral or rock fragments, regardless of size:
- Organic matter: Decaying plant or animal matter (humus).
- Soil: A complex mixture of mineral particles, organic matter, water, and air.
- Pure chemicals: Single-element or single-compound substances, like pure salt (NaCl) or sugar (C12H22O11).
- Water: H2O in liquid, solid (ice), or gaseous (steam) form.
- Air: A mixture of gases (nitrogen, oxygen, argon, etc.).
- Petroleum products: Oil, gasoline, asphalt, etc.
- Rubber: Natural or synthetic rubber materials.
- Textiles: Fabric made from natural or synthetic fibers.
- Paper: Material made from cellulose pulp.
- Living organisms: Bacteria, algae, plants, animals.
- Concrete: A composite material made of cement, aggregates (sand, gravel), and water.
- Asphalt: A mixture of aggregates (sand, gravel) and bitumen (a petroleum product).
In summary, anything that doesn’t fit the particle size range of 0.0625 to 2 mm and isn’t primarily composed of mineral or rock fragments is not sand. This includes materials that are too fine (silt, clay), too coarse (gravel, pebbles), or composed of entirely different substances (organic matter, plastic, water).
Pray This Prayer
Oh, Spirit of the Everything,
Forgive our clinging to the grains. We gather them, build empires upon them, believe them to be permanence. But even sand, so vast, so seemingly endless, is subject to the wind, the waves, the relentless turning of time.
What is not sand? Show us, we pray. Show us the bedrock beneath the shifting dunes. Show us the water that carves canyons through the desert. Show us the unwavering light of the sun that warms both sand and stone.
Grant us the wisdom to see beyond the surface, to recognize the true substance, the unshakeable foundation upon which all things rest. Help us to find strength in that which is not fleeting, not ephemeral, not subject to the tides of fortune.
May we build our lives not on the shifting sands of materialism, ego, or fear, but on the solid ground of love, compassion, and truth.
Open our hearts to the vastness that lies beyond the perceived limitations of our senses. Let us feel the power and resilience of that which is not sand: the spirit within, the connection to all things, the unwavering hope that burns even in the darkest night.
Amen.