If you have found sand dollars on the beach, you should clean them before displaying or painting them. The remains of these sea urchins dry naturally in the sun. You can rinse them with fresh water to get rid of any sand or debris and let them soak in a bleach solution to speed up the bleaching process. Do not collect live Clypeasteridae: not only is it cruel, but also illegal in some areas.
Steps
Part 1 of 3: Collect the Sand Dollars
Step 1. Do not collect live curls
It is considered cruel to kill these animals for the sole purpose of drying them and using them as decoration. If everyone did, the sand dollar population would suffer dramatically and eventually no one could find their shells anymore.
- Do not take them directly from the sea. The Clypeasteridae are animals related to sea urchins and starfish, they hide under the sand of the seabed to protect themselves from predators and debris. If you take a dollar of sand off the sea bed, there's a good chance it's alive.
- Flip the shell over for thin legs or millipede-like hairs on the underside. Gently tease them with your finger; if they move, the animal is alive and you should put it back in the water; if not, feel free to pick it up and take it home.
- If it is wet or heavy and "full", it is probably alive or recently dead, even if you found it on the beach. In these cases, rely on common sense and opt to put it back into the sea if in doubt.
Step 2. Collect the dried exoskeletons that were thrown onto the shore by the waves
The rarity of the finds of these shells makes their discovery even more significant and you know for a fact that you are not capturing and killing a live animal.
- In many states it is illegal to collect live sand dollars, and if caught red-handed, you could be fined. If you don't know the law - or if you care about conserving the fragile coastal ecosystem - don't take these urchins straight from the water.
- Many coastal authorities set a maximum number of Clypeasteridae that can be harvested at one time. Research laws and regulations before preparing for a day on the beach.
Part 2 of 3: Cleaning and Drying the Sand Dollars
Step 1. Be gentle when washing these shells
They are actually fragile exoskeletons that break easily if handled carelessly.
- Don't rub them too hard; if you have decided to clean them this way, don't apply too much pressure.
- Don't soak them in chemical solvents - such as bleach or acids - for too long. The solvent can deteriorate this already very delicate object. Clean the sand dollar, but don't dissolve it!
Step 2. Remove the rotting material
If the shell was recently thrown onto the beach by the waves, it may still contain residues of the dead animal. You can let the sand dollar dry naturally in the sun, bury it and let the insects feed on the traces of fabric, or remove these parts by hand.
- If you perceive a musky, salty smell around the hedgehog, similar to that emitted by rotten algae, there may be decaying animal tissue.
- Expose the exoskeleton to the sun for a few weeks; in this way, the soft tissue residues degrade naturally and disappear. Additionally, the sand dollar begins to slightly whiten and harden. When it has a shell-like appearance with a rather smooth surface, it is ready to use.
- Consider burying it in the soil in your garden or vegetable garden. You can put it at any depth that is greater than 5-6cm. Within a week or two, worms and other detritivores in the earth consume dead tissue leaving a perfectly clean sand dollar. Remember to identify the area where you bury the exoskeletons with a particular stone or stake so as not to forget it. Be careful not to crush the sea urchin when you bury it or dig it up to bring it back to the surface.
- You can remove the remains of the animal with a sharp pocket knife. Remember that the tissues have developed inside the exoskeleton and it may be difficult to extract the last pieces. If you have decided to use a knife, be careful not to cut yourself or scratch the surface of the Clypeasteridae. You should expose the shell to the sun for a few days, even if you have cleaned it by hand.
Step 3. Rinse off the sand dollar
Soak it in clean, fresh water to get rid of any sand or debris that has become stuck in it.
- Fill a bowl or bucket with fresh water and leave these sea urchins soaking until the liquid turns cloudy and brown; replace it with fresh, clean water and continue soaking the shells until the water is dirty again. Repeat the process until it remains transparent.
- If the exoskeleton is particularly dirty, you can add a couple of squirts of dish soap to the water for a slightly more aggressive cleaning mixture. If you are in a hurry, you can continue rinsing the shells under cold running water until it runs clean and without sand.
- Consider using a stiff bristle brush to remove sand from cracks, crevices, and cracks in the shell. You have to be very gentle - sand dollars are extremely fragile and cannot withstand too vigorous action.
- When they are cleared of sand, expose them to the sun for several hours to dry.
Step 4. Remove the tar from the shells
Some beaches are known for the sticky black tar that is washed ashore by the waves and covers the pebbles, sand and feet of the people who walk there. If the sand dollar is tarred, you can't clean it with water alone.
- Peel off each large piece of tar with a sharp piece of metal, such as a paint scraper or knife. Be careful not to injure yourself and not to scratch or break the hedgehog's exoskeleton. It is best not to use force with these shells, as they are so fragile.
- Use baby oil. Spray a small amount of this substance on the surface of the hedgehog and scrub the area covered with tar carefully. If you don't want to get your fingers dirty, use a handkerchief or the corner of an old tea towel. Keep scrubbing until baby oil begins to dissolve the tar; within a few minutes you should be able to remove most of them.
- Consider using any of the following tar "thinners": eucalyptus oil, lard, margarine, olive oil, mineral oil, peanut butter, petroleum jelly, seed oil, or suntan cream. Try adding them to the bowl of water in which you soak the sand dollars and then coat the shells with these pure "softeners" in another container.
Part 3 of 3: Whiten and Store Sand Dollars
Step 1. Soak them in a bleach solution
If you want the exoskeletons to be even whiter or are having trouble cleaning them with water alone, you can consider bleach. Mix it with an equal amount of water and put the Clypeasteridae in the solution.
- If you are cleaning numerous specimens, fill a baking sheet with the mixture of water and bleach; this allows you to arrange the various shells evenly over a large surface. Make sure the sand dollars are completely submerged in the liquid. Alternatively, you can use a bowl, bucket, or Tupperware-type container.
- If you are cleaning only one exoskeleton, find a small bowl, lid, or other container; you won't need a lot of bleach to get the effect you want.
- Be careful not to leave the sand dollars to soak for too long - the shell will begin to soften and disintegrate if it remains in excessive contact with this strong solution. If you want to wash them for a longer time, reduce the concentration of the mixture.
- Be cautious when handling bleach. Make sure it doesn't get into your eyes and don't swallow it. Wash your hands with soap and water after touching them.
Step 2. Rinse the shells after bleaching them
Transfer them to a bowl or tray filled with fresh water.
- Bleach continues to corrode sand dollars even after removing them from the liquid; you must therefore rinse them thoroughly to neutralize the solution and eliminate the last traces of dirt.
- When you are sure the shells are clean, leave them in the sun to dry them. Within a few hours they should be ready to be decorated, displayed or kept as a souvenir. These exoskeletons get tough over time, but you need to keep handling them carefully.
Step 3. Consider making them stronger with glue
This solution is very practical if you intend to use the exoskeletons in a craft project or if you want to expose them without the risk of them breaking.
- Mix the white glue and water in equal parts. Use a sponge or brush to completely coat the shell with the mixture. Wait for the glue to dry and become hard like icing.
- Sand dollars naturally get hard over time as they dry out more and more. Remember that denser glue mixes can hide the natural texture of shells.
- When exoskeletons are hard and dry, you can use them for your projects or expose them. Paint or decorate them, give them away or leave them as they are.
Advice
- Handle the remains of these animals with great care, especially the smaller ones, as they chip or break easily. Try not to drop them and do not manipulate them violently.
- You can find most of the Clypeasteridae along the shores of the sea. When alive, they hide under the soft sand of the seabed. When they are dead or dying, they are pushed onto the beach where they dry out in the sun.
- In some countries it is illegal to collect live sand dollars. Do your research and be respectful of animal life.
