Trilobite Fossil Site

• General Information
• Directions to Amboy
• Directions to the Mountain
• Directions to the Fossil Site
• Finding Trilobites
• Tools and Equipment Required
• Rules and Regulations
• Further Reading

This beautiful fossil site is located near the base of a mountain in the Marble Mountains range, located 2.4 miles from the historic Route 66 in the Mohave Desert of San Bernardino County of Southern California.

This is an outcrop that spans from the Cambrian to the Devonian Periods. It is one of the oldest outcrops in California that yields fossils. The trilobites are located in a 60 feet thick formation named the Latham Shale close to the base of the mountain and inside the Early Cambrian age (approx. 560 million years ago).

Trilobites, one of the first animals with eyes and skeletons on earth, were small marine crustaceans whose general body design closely resembled that of the existing horseshoe crabs.

Amboy can be reached via Barstow by taking Interstate 40 until Ludlow (approx. 45 miles). There you take the historic Route 66. Amboy is approx. 30 miles from Ludlow.

Amboy has two landmarks: an extinct volcano crater and a Gas Station / Motel / Cafe located along Route 66. If you are not planning on camping in the desert near the fossil site, I will recommend you make this place your center of operations while you dig the trilobites.

The Motel is decent and appropriate for this kind of adventure. Each room has two full beds and air conditioning.

From Amboy, take Route 66 East for approximately 10 miles until you reach a road that goes to the town of Cadiz. That road intersection is the old locality of Chambless. There is no much left there, except for an abandoned store at the right hand side of Route 66.

The mountain is about 2 miles Northeast of the abandoned store. The fossil site (red) is in the East slope of the third of four ridges extending Southeast. To get there you must drive in desert trail roads and park near the base of the fourth ridge (yellow). It is possible to take a family car to the parking site, but a 4WD sport utility vehicle is recommended.

Once you get to the base of the fourth ridge you will need to hike for about 3/4 miles with a steeper 100 yard climb at the end. You must hike Northwest towards the East side of the third ridge of the mountain. If you go directly ahead (yellow) you will need to cross several gullies. If you want to avoid deep gullies at the expense of more walking, you can detour Southwest to where the gullies are not so deep (blue), then turning Northeast and hike up to the collecting area (red).

The Latham Shale is a 60 feet thick formation below a very defined marker formed by a tilted row of dark brown rocks (arrow). The fossil site area is easy to find. You will find many quarry holes with pieces of shale laying along the slope.

Once you are in the Latham Shale formation, you will see quarry holes and a high amount of pinkish, dark green and light brown shale spread along the hillside.

You can quarry or just inspect and split the shale lying around. Remains of trilobites, mostly cephalons (heads) and thorax segments are abundant. Slabs with complete specimens have been discovered by just splitting the shale found along the slope.

In about an hour, you will find several trilobite remains, mainly from the species Olenellus Clarki. In about two hours, you will have an excellent chance of finding a complete trilobite - an animal that was alive where you are standing more than 550 million years ago!

• Compass
• Geological hammer
• Chisel
• Goggles (important when splitting shale)
• Gloves (always use them to protect you from any scratches and bugs)
• At least 1 gallon of water per person per day
• Camping equipment and supplies (optional)
• Video and/or photo camera (you need to record this adventure!)
• Cellular phone (just in case of any car or other emergency - a two plus miles hike in a dry desert is tough!)

This adventure requires of moderate driving, hiking, climbing, and/or camping in a wild and dry desert area located over two miles away from Route 66. Anyone that decides to visit this fossil site does so at his own responsibility.

The site, officially named "Trilobite Wilderness Area", its within authority of the Bureau of Land Management located in Needless. Permits are not required for the casual fossil collector. You must respect the area. Do not dig indiscriminately. You must clean-up and carry all your garbage with you. Take with you a maximum of two fossils per person. Please be aware that this fossil site is a gift from nature for everyone to enjoy.

If you find an unusual fossil, please contact your nearest museum of Natural History. If you discover a new species, it will be named after you!

The following books are recommended for further reading:

• "Wonderful Life" by Stephen Jay Gould, W.W. Norton & Company, New York, 1989. Describes in detail the Middle Cambrian Burgess Shale fauna and theorizes about the amazing improbability of vertebrate life ever dominating the world. HIGHLY RECOMMENDED
• "Trilobites" by Riccard Levi-Setti, The University of Chicago Press, 2nd edition, 1993. One of the best books on Trilobites. Many beautiful photographs with several Olenellus trilobites specimens collected at the Latham Shale. ( Click on book titles to link to Amazon.com )