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Hints for Rock Collectors From The U.S. Geological Survey

  1. Label specimens as they are collected. Identification can wait until later but the place where rocks were found should be recorded at once. Many collections have become mixed because the collector did not do this.
  2. For displaying your specimens, trim rocks in the collection to a common size. Specimens about 3 by 4 by 2 inches in size are large enough to show rock features well. Other display sizes are 2 by 3 by 1 inch, or 3 by 3 by 2 inches.
  3. Ask for permission to collect rocks on private property. The owners will appreciate this courtesy on your part.
  4. Be careful when collecting rocks. Work with another person if possible and carry a first aid kit. Wear protective clothing, safety glasses, hard-toed shoes, hardhat and gloves when dislodging specimens. Avoid overhanging rock and edges of steep, natural or quarried walls.
  5. Do not collect rocks in national parks or monuments, not in state parks; it is illegal. Similar rocks commonly crop out on land nearby.
  6. Look for unusual rocks to study in large buildings or in cemeteries. Dimension stone blocks and monument stone are often transported long distances from where they are quarried. Polished stone sometimes looks different from unpolished rock. This provides good identification practice.
  7. Join a mineral club or subscribe to a mineral magazine--a good place to discuss and learn about rocks.
  8. Collecting rocks from each state or country has no scientific significance. The distribution of rocks is a natural phenomenon and is not related top political divisions.

The San Francisco Gem & Mineral Society, Inc.

4134 Judah Street

San Francisco, CA 94122


Guests and visitors are welcome at all meetings which are usually held
on the first Friday of each month, 8 pm at the clubhouse.

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