Home   Calendar   Holidays   Old Rock Day

Jan7 Fun Holiday – Old Rock Day

January 7 is Old Rock Day. The unofficial holiday encourages people to acknowledge, celebrate, and learn more about old rocks and fossils.

Ammonite fossil.

Old rocks can contain fossils.


A rock is a solid mass made of minerals or mineral-like substances. Used for a variety of purposes throughout the history of humankind - as tools, musical instruments, weapons and for mining - rocks form the outermost layer of Earth.

A Peek Into Earth's History

While natural processes - volcanic eruptions and erosion - continually help create rocks on Earth, old rocks are especially important to those who study the Earth and its history. Old rocks hold many answers to the mysteries of Earth's formation - they can tell scientists about natural events that played a role in the formation of the rocks and the effects that event had on other life forms in the area.

Old rocks can also sometimes hold fossils - the preserved remains of animals, plants and other organisms. These fossils can help scientists find out the kind of flora and fauna that existed in the past and what may have caused them to evolve or go extinct.

Finding the Age of Old Rocks

Geologists date old rocks using a technique called radiometric dating or radioactive dating. The process involves looking at the decay of radioactive elements available in rocks. The oldest rock of terrestrial origin to be dated using this method is a zircon found in the Jack Hills of Australia. Scientists estimate that the rock could be as old as 4.4 billion years.

How to Celebrate?

  • Learn more about the types of old rocks.
  • Pick up a book about fossils and learn how fossils tell us more about the Earth’s past or visit your local natural history museum.
  • Take a walk in the park and collect interestingly shaped rocks.
  • Buy your loved ones some pretty looking rocks. And by rocks, we mean jewels. After all, diamonds are old rocks.
  • Looking for a new hobby? May we suggest collecting rocks?
  • Find rocks boring? Listen instead to music from old rock bands.

Did You Know…

...that Petrology is the scientific study of rocks?

Old Rock Day Observances

Fun Holiday: Old Rock Day Observances
2024SunJan 7Old Rock Day
2025TueJan 7Old Rock Day
2026WedJan 7Old Rock Day
2027ThuJan 7Old Rock Day
2028FriJan 7Old Rock Day
2029SunJan 7Old Rock Day
2030MonJan 7Old Rock Day
2031TueJan 7Old Rock Day
2032WedJan 7Old Rock Day
2033FriJan 7Old Rock Day

See all Fun Holidays

Other Fun Holidays around January 7

5 Jan

Bird Day

Celebrate birds and ensure that avians around the world are treated humanely.

6 Jan

Bean Day

Beans are healthy and delicious. Add them to your daily diet starting today.

8 Jan

Earth's Rotation Day

Celebrate the anniversary of the day in 1851 when it was shown that the Earth rotates on its axis.

8 Jan

Clean Off Your Desk Day

Celebrate this productive and fun holiday by keeping your workspace clean and clutter free.