Petrified wood is a fascinating fossil with unique beauty and natural history. It undergoes mineralization, replacing organic material with minerals to form a rock-like structure.
Today, we will explore the origins, formation, uses, legalities, identification, and more about Petrified Woods.
Whether you’re a collector, decorator, or simply curious about natural history, this article provides essential facts about these ancient specimens.
Jump To a Section Below
- What is Petrified Wood?
- History of Petrified Wood
- Where Can You Find Petrified Wood?
- How Is Petrified Wood Formed?
- Physical Properties
- Cause of Coloration
- How To Identify Petrified Wood?
- Is It Legal To Collect Petrified Wood?
- Is Petrified Wood Rare?
- Petrified Wood Value
- What’s Petrified Wood Used For?
- Other Types of Fossilized Wood
- Final Thoughts
- FAQs
What is Petrified Wood?
Petrified wood, also known as Petrified Tree, is a form of fossilized wood in which minerals have replaced the organic material, resulting in a preserved section of a tree trunk that maintains the same shape and patterns as its past organic form.
It can form in several ways and can consist of different materials other than regular wood. Petrified wood is different from other fossilized wood because of how it is formed. It can be found in different forms, like wood in sunken forests or preserved wood.
History of Petrified Wood
The preservation of fossilized tree remains dates back millions of years, with petrified wood samples dating from the Paleozoic Era (570-240 million years ago), Mesozoic (240-64 million years ago), and Cenozoic (Eras 65 million years to present).
Petrification takes thousands of years and results in a durable material that can withstand the test of time. Petrified wood can definitely provide valuable insights into the geological history of the earth, including information about past climates and ecosystems.
Where Can You Find Petrified Wood?
The Petrified Forest National Park in Arizona is a popular destination for seeing petrified wood, but it is illegal to collect fossils or natural items from national parks.
Other states in the US where petrified wood can be found include Washington, Oregon, Texas, Louisiana, Mississippi, South Dakota, California, and Colorado.
Each location has its own variety of species, such as ginko, cypress, oak, and palm wood, which have been preserved through the petrification process.
Countries like Australia offer peanut wood, a type of petrified driftwood, while Madagascar has petrified wood in a range of colors with well-preserved tree rings.
How Is Petrified Wood Formed?
Through the process of rapid burial and subsequent mineral replacement, the organic matter of wood can be transformed into a stunning fossil. When wood is quickly buried, an oxygen-poor environment is created that prevents decomposition by bacteria and fungus.
Groundwater, rich in minerals, can then flow through the material and replace the organic matter while preserving the wood’s unique features. Alternatively, water can dissolve the wood away, leaving a cavity that is then filled with minerals to create a cast.
If you wanna read more about it, head on to the Formation Process of Petrified Wood.
Physical Properties
- Major Mineral: Chalcedony, sometimes Opal (Wood Opal)
- Cleavage Quality: None
- Refractive Index: Approximately 1.54
- Birefringence: Weak or None
- Pleochroism: Absent
- Dispersion: None
- Transparency: Opaque to Translucent
- Crystal System: Trigonal
- Habit: Microcrystalline aggregate
- Color (General): Mostly dull gray or brown, sometimes red, pink, light brown, yellow, and even blue to violet.
- Mohs Hardness: 6.5 to 7
- Specific Gravity: 2.58 to 2.91
- Fracture: Uneven, Splintery
Cause of Coloration
Colors in petrified wood are caused by the presence of different compounds or elements, such as iron oxides, manganese, manganese dioxide, and iron, copper, cobalt, or chromium.
The red, grey, brown, and yellow hues are attributed to iron oxides, while pinks and oranges come from trace amounts of manganese. Manganese dioxide is responsible for the purple and blue coloration, and shades of green can be attributed to chromium.
Interestingly, petrified wood from Arizona is known for having a wide range of colors on individual specimens, which is caused by different oxidation states of Iron, the dominant coloring element for petrified wood samples from Arizona.
How To Identify Petrified Wood?
To identify petrified wood, one must observe the specimen’s edges, absence of bark, growth rings, and patterns, as well as evaluate its transparency for light passage.
Another way to identify is by getting a closer look at the petrified wood, you can use a microscope or a magnifying lens. Look for lines called rays, check the patterns of wood cells, observe the colors present, and look for resin ducts.
Here’s our full guide on How To Identify Petrified Wood.
Is It Legal To Collect Petrified Wood?
The legality of collecting petrified wood is a crucial concern for those interested in obtaining specimens, as it is a fossil that is legally protected in the United States.
Collecting can only be done on private property with permission from the landowner or on limited tracts of government land where small quantities are allowed for personal use.
It would be best to get permission and rules from the owner or government agency before collecting. The risks of collecting without permission include fines, imprisonment, and damage to natural resources.
Is Petrified Wood Rare?
Low-quality Petrified Wood or those that can easily break or chip is not rare, in fact, Petrified Wood in general is not rare at all, however, gem–quality ones are extremely rare and valuable since only a small proportion can be cut and polished into gemstones.
Petrified Wood Value
The price of Petrified Wood can vary greatly. The rarest pieces can be sold for over $100,000, while smaller ones can be found for less than $50.
What’s Petrified Wood Used For?
Petrified wood is a popular material in lapidary work, where it is cut into various shapes for making jewelry, bookends, table tops, and even clock faces. However, only a small fraction of petrified wood is suitable for such purposes, as poorly preserved specimens do not polish well or can break easily.
The most highly prized specimens are those with no fractures or voids and with spectacular color.
Aside from its industrial uses, Petrified Wood is also being widely used in metaphysical practices, here’s where you can read more about it.
Other Types of Fossilized Wood
Aside from the most popular Petrified Wood, here are some other types of Fossilized Wood.
- Opalized Wood: Opalized wood is fossilized wood that has been replaced by opal. The replacement of the wood with opal creates a unique play-of-color effect, often resulting in vibrant and iridescent hues.
- Jet: Jet is a type of fossilized wood that is composed of decayed wood that has been compressed and undergone a process called carbonization. It is usually black or dark brown in color and has been used for centuries in jewelry and ornaments.
- Lignite: Lignite, also known as brown coal, is a low-grade form of coal that can contain fossilized wood. It is a sedimentary rock formed from partially decomposed plant material, including wood, in swampy environments.
- Coal: Coal is a fossil fuel formed from the remains of ancient plants, including woody material. Over millions of years, heat and pressure transformed the plant material into coal. It is commonly used as a source of energy.
Final Thoughts
Petrified wood is a fascinating geological phenomenon that has captured the attention of many. Petrified wood is ancient wood that has turned into stone over millions of years.
It comes in different colors due to minerals present during the fossilization process. People use it for decoration, furniture, and sometimes for spiritual reasons.
Identifying petrified wood can be challenging, but texture, pattern, and weight can help. There are different types of petrified wood with unique properties.
Overall, petrified wood is a fascinating geological wonder that captivates people worldwide.
FAQs
Is Petrified Wood older than dinosaurs?
Yes, to be exact, there are a lot of specimens that are older than dinosaurs, but they can also form relatively quickly, in 5,000 to 10,000 years compared to older specimens which took millions of years.
Can petrified wood get wet?
Petrified wood can get wet, but it’s important to dry it properly to prevent damage.
Is petrified wood radioactive?
In general, petrified wood is not radioactive, but some rare specimens contain very little radiation that doesn’t pose a threat to humans.
Chermaine’s journey into the world of gemstones and crystals began as a child, collecting shimmering stones on family vacations. Today, she’s a certified gemologist and spiritual healer, intertwining the physical beauty of jewels with their metaphysical properties.
Chermaine has traveled to mines in Africa, marketplaces in India, and spiritual retreats in Bali, always seeking to deepen her understanding.