Where is Coral found?
Anthozoa (calcium carbonate skeleton)
Got a photo? Identify rocks instantly with the Rockby app
Open the appCoral occurs in specific geological environments. Knowing where to look, and in what kind of rock, is the difference between going home empty-handed and finding a great specimen.
Where to find Coral
Great Barrier Reef, Australia
The world's largest coral reef system, showcasing diverse modern coral species.
Caribbean Sea
Home to numerous coral reefs, including those off the coasts of Florida, Belize, and various Caribbean islands.
Indo-Pacific Region
Includes the Coral Triangle (Indonesia, Philippines, Malaysia, Papua New Guinea, Solomon Islands, Timor-Leste), a global center of marine biodiversity and coral diversity.
Mediterranean Sea
Known for precious red coral (Corallium rubrum) in deeper waters.
Florida, USA
Fossil coral (agatized coral) is found in various localities, particularly in the Tampa Bay area, often designated as the state stone.
Indonesia
A significant source of both modern and fossil coral, including 'sponge coral' and agatized varieties.
Collecting tips
- Modern Coral Collection. Collection of living or recently dead coral is strictly regulated or prohibited in many areas due to conservation efforts. Always check local laws and regulations before attempting to collect any coral material. Only collect legally obtained, sustainably sourced, or fossilized coral.
- Fossil Coral Identification. Look for distinct patterns of corallites (individual polyp cups) or colonial structures preserved within sedimentary rocks. Agatized fossil coral will often have a waxy luster and conchoidal fracture, with the original coral structure visible as a pattern within the chalcedony.
- Acid Test (Caution). Coral, being calcium carbonate, will effervesce (fizz) when a drop of dilute hydrochloric acid is applied. This test should be performed cautiously on a small, inconspicuous area as it can damage the specimen. This test is less effective for agatized fossil coral, which is primarily silica.
- Geological Context. Fossil coral is typically found in marine sedimentary environments, often associated with ancient reef structures or shallow marine deposits. Look for it in limestone quarries, coastal exposures, or river gravels that have eroded from such formations.
Quick Check
- Color:
- White, red, pink, orange, blue, black, brown (modern); varied, often patterned (fossil)
- Luster:
- Dull to waxy/vitreous
- Streak:
- White
Explore Coral
Identify rocks anywhere
Free on iOS, Android, and Web. Photo identification, full database, and your personal collection.