Before you start to collect, be sure to ask the owner’s permission to go on his property. If he agrees to let you come on his land, be careful about closing gates, and do not leave holes into which his livestock might step and be injured. Look out for snakes. Plenty of rattlers, copperheads, and moccasins are still left in Texas. And, incidentally, collecting is not allowed in State or National parks. To identify the rocks and minerals that you collect, you probably will need several articles with which to make simple tests. The following can be easily obtained: 1. A _pocket knife_, a _copper penny_, a piece of _window glass_, a _steel file_, and a piece of _quartz_ to test the hardness. If you prefer to use a group of minerals of known hardness, such as those of Mohs scale described on pages 16-17, you can either collect your own or buy a prepared set from a mineral supply house. 2. A _streak plate_ to test the color of the mineral’s streak. Mineral streak plates can be purchased, or a piece of unglazed tile can be used. 3. A _magnifying glass_ to examine small cleavage surfaces, crystals, and rock grains. A number of different kinds can be bought, from the simple reading glass to the precisely made hand lens. A lens with ten-power magnification is good for general use. 4. A small _magnet_ to test whether or not a mineral is magnetic. 5. _Dilute_ (10%) _hydrochloric acid_ (HCl), also known as _muriatic acid_, to test carbonate rocks and minerals. You can buy a small bottle at a drug store. Be extremely careful in handling this acid, and keep it away from small children—it is a _POISON_. If you spill any on yourself, it will burn your skin and eat holes in your clothes. [Illustration: Hand lens.] The rock and mineral identification charts on pages 24-41 will help you to make the simple identification tests in a methodical way. It is a good idea to have some system of labeling your rock and mineral specimens. Some collectors carry note paper with them on field trips. Then they can write down the location and, if possible, the name of the rock or mineral. This information is either wrapped with the specimen or stuck to it with tape. One way to label large collections is to put a small spot of paint or fingernail polish on each of the rock and mineral specimens. When the paint has dried, a number can be written on it in black India ink. Then, on a file card, the name and the number of the specimen can be written, together with the place where it was found, the date of collection, and the name of the collector. ROCK AND MINERAL IDENTIFICATION CHARTS