top of page
Image by Billy Huynh
Sylvia Rose

Algae in Glass Houses: Diatomaceous Earth

Diatomaceous earth (DE) is an amazing natural powder ground from the sedimentary stone diatomite. The stone itself is made of fossilized diatoms, microscopic algae entities with shells of silica glass. Diatomaceous earth comes from millions of years of natural processes.



Diatomite a rock of fossilized shells
Diatomite, a soft rock made of diatom glass shells

Diatomaceous earth is an organic product found in the local hardware store or plant nursery, often used for insect pest control. Insects dry out and die when exposed to diatomaceous earth, as it absorbs oils and fats from the cuticles of their exoskeletons.


The abrasive sharp edges of diatomaceous earth accelerate this process, cutting the insect to pieces as it struggles to escape its pitfall of death. The earth's effectiveness lasts as long it's dry and undisturbed. Diatomaceous earth of course kills beneficial as well as harmful insects.



beautiful butterfly on the ground

Diatomite & Components of Diatomaceous Earth


Diatomaceous earth is primarily made of skeletal remains of diatoms, unicellular algae of diverse shapes, characterized by unique silica-rich cell walls. Diatoms actually live in glass houses. When they die, their remains accumulate at the bottom of salt or freshwater bodies.


Over eons, the weight of overlying sediments compresses these layers. Lithification involves chemical and physical changes to transform them into the rock diatomite.


The principal component of diatomaceous earth is silica, which accounts for approximately 80-90% of its composition. Silica creates the white color of the stone.



Electron microscope, diatomaceous earth
Electron microscope, diatomaceous earth

It also contains traces of other elements such as aluminum, calcium, sodium, iron and magnesium, along with organic matter. Its unique texture and porous nature come from the microstructure of diatom skeletons, which provide high surface area and low density.


Diatomite is found in deposits worldwide. High-quality diatomite is prized for its purity and high silica content and finds applications in industries like food filtration and agriculture. Some diatomite deposits can be thousands of feet thick.


Diatoms - Crucial to Life on Earth


Diatoms have existed for over 100 million years. Widespread in the world today, they live even in Antarctica. Types of one-celled phytoplankton, they inhabit fresh and marine waters. They're characterized by their ornate silica cell walls, or frustules, which form in many shapes.



Fossilized Diatom triangular skeleton
Fossilized Diatom triangular exoskeleton

Diatoms are indispensable to ecosystems worldwide. They form a crucial part of the aquatic food chain, serving as a primary food source for many marine organisms, such as zooplankton and small fish.


Diatoms convert carbon dioxide into organic matter through photosynthesis. This process not only forms the base of aquatic food webs but also contributes to most of the oxygen production on Earth.


How Diatoms Make Silica


Diatoms produce silica through a process called, not surprisingly, silicification. Using dissolved silica found in aquatic environments, diatoms create unique cell walls by absorbing and metabolizing the silica into solid form.



Leaf-shaped Diatom glass remains
Leaf-shaped Diatom glass remains

Originating over 200 million years ago, diatoms are among the most common forms of phytoplankton found in oceans, rivers, and lakes. These organisms make silica cell walls fit together like two parts of a petri dish. This composition gives them structural strength. They can also adapt to changes in silica availability.


Uses of Diatomaceous Earth


Filtration: DE is widely used in water treatment and filtration systems due to its ability to filter out impurities and particles without clogging. It's a effective in industries like water purification, swimming pool maintenance and brewing. Its porous structure allows it to trap particles and contaminants efficiently.



Water Purification
Purified Water

Pesticide: As a natural pest control agent, diatomaceous earth can be sprinkled around gardens to kill insects. Diatomaceous earth kills pests such as ants, bed bugs, and cockroaches. The sharp edges of the fine powder damage the exoskeletons of these insects, leading to dehydration and death.


Absorbent: The high porosity of DE makes it an excellent absorbent material, used in products such as cat litter, industrial spill cleanup, and as a drying agent in various applications.


Food Industry: Food-grade DE is used as an anti-caking agent in powdered foods and filters for beverages like beer and juice.


Cosmetics and Skincare: With its micro-abrasive qualities, diatomaceous earth is included in some beauty products for exfoliation. Some advocates claim food-grade diatomaceous earth may have benefits such as improved digestion and skin health. DE is used in toothpaste and facial scrubs for its abrasive properties.



Complexion treatment
Complexion treatment

Construction: DE is used in building materials for insulation and as a filler in construction products.


Facts About Diatomaceous Earth


Non-toxic: Food-grade diatomaceous earth is deemed generally recognized as safe (GRAS) by the FDA and is non-toxic to humans and pets. However, due to sharp silica fragments, don't breathe it in.


Sustainable resource: As a naturally occurring material, diatomaceous earth can be sustainably harvested without depleting ecosystems, at least for a while.


Global Deposits: Significant deposits of diatomaceous earth can be found in places like the United States, Europe, and parts of Asia, from ancient lakes and seas.



walking across a dry wadi

Eco-Friendly: DE is classified safe for the environment and acceptable for organic farming practices.


Non-Toxic: Food-grade diatomaceous earth is classified safe for human consumption.


Angular Structure: The sharpness of diatomaceous earth’s particles makes it an effective natural insecticide for pest control.


Historical Use: Diatomaceous earth has a rich history of use, including as a building material of the ancients.



Food Grade Diatomaceous Earth
Food Grade Diatomaceous Earth

Non-Fiction Books:


Fiction Books:

READ: Lora Ley Adventures - Germanic Mythology Fiction Series

READ: Reiker For Hire - Victorian Detective Murder Mysteries





Recent Posts

See All
bottom of page