Most of us enjoy a variety of foods that contain lots of salt. These include processed meats, pizza, cheese, bread, potato chips, and fast foods. Salt adds flavor to foods and helps to preserve them. This is why many foods that you get at restaurants and grocery stores that are prepackaged or canned have so much salt in them.

Salt is essential for life. Salt is a mineral substance, primarily sodium chloride (NaCl).  It’s produced by mining it from salt mines or by allowing water to evaporate in small pools, leaving the salt behind.  It’s needed by our bodies to keep the fluid in our cells and to help transmit messages throughout the nervous system.

Too much salt in your body, however, causes your heart and blood to pump faster and harder to remove the extra salt that your body doesn't need. This makes your blood pressure too high over time, and can make you unhealthy.

Salt is also a natural disinfectant, which means it can kill germs. If you have ever had a sore throat, maybe you have gargled with salt water to soothe and heal it. Salt can also help wounds or sores heal on your body.

So we know we often crave salty foods, but what else do we know about salt? Here’s a little history.

Because many germs cannot live in salt, it has been used to preserve food since the earliest times. Its use as a food preservative helped large amounts of food to be stored, sent a long way, and eaten all through the year. This helped populations to grow, cities to develop, and soldiers in wars to be fed. Salt was probably used in Egypt as long ago as 4000 BC.  In ancient times, salt was more valuable than it is now, because it was hard to get in many places, and could be used not only to give foods flavor, but also to make them last longer. It allowed food to be kept past its season, and taken on long trips.

People often traded salt for other things. It was of high value in Greece, China, Africa, and the Middle East. In the Mediterranean, including Ancient Rome, salt was even used for money. The word salary comes from the Latin word for salt, because they paid people in salt. After people learned how to get salt from the ocean, salt became cheaper. The Phoenicians were some of the first to figure out how to do this, by pouring seawater on dry land. Then when it dried, they collected the salt and sold it.

Another use of salt was in war, as a way to punish a city by ruining its crops. This is called "salting the Earth." The Assyrians are said to have been one of the first to have done this to their neighbors.

China and the US are the biggest producers of salt in the world, with about a third of the US production coming from salt mines. The rest is from the saltwater evaporation method. The largest salt mine in the world exists underneath Lake Huron.

Finally, table salt consists of tiny cubes, or crystals, tightly bound together through bonding of the sodium and chloride ions. Sodium chloride is available in several different particle sizes and forms, depending on what the intended end use is.

Different types of crystals also have different uses. You can see the crystals in rock salt used for de-icing. Fine granules are typical of what is used for table salt and even finer popcorn salt. Kosher salt, pickling salt, and ice cream salt are slightly coarser. Small compressed pellets are what is used in water softeners and large salt blocks are what is used as salt licks for livestock.

This month we feature the Quirkles® book Ronnie Rock and conduct the activity Ronnie Rock’s Crystals. Watch our video to learn more. And next time you reach for the lowly salt shaker, take time to appreciate salt!

If you live close to an ocean, maybe you plan one more trip as summer winds down. Or if you live elsewhere, you may dream of your next trip to the seashore once things return to some sort of normal. Despite being beautiful and soothing to the soul, oceans are awesome in many other incredible ways, too. Here are six surprising facts you maybe didn’t know.

*About 70 percent of the Earth's surface is covered with water, yet the oceans largely remain a mystery for scientists. More is known about the Moon's surface than the depths of the ocean. In fact, 12 people have stepped foot on the Moon, but only three have been to the Mariana Trench—the deepest part of the ocean, roughly seven miles deep.

*Though 94 percent of life on Earth is aquatic, about two-thirds of all ocean life is still unidentified. New species are constantly being discovered. Recently a red species of sea dragon that lives in shallow waters off the western coast of Australia was discovered. Other new finds have included what may be the world’s ugliest fish, as well as a ghostly octopod and a “ninja” shark with a dimly glowing head.

*It's not just the sea life of the oceans that remain mysterious to scientists; there are also sounds that scientists cannot explain with any certainty, either. “The Bloop” may be the most famous underwater sound, captured in 1997 by hydrophones set out by the National Oceanic and Atmospheric Administration (NOAA). It is one of the loudest ocean sounds ever recorded, and while the noise is consistent with a large iceberg fracturing, no one knows for sure what made the sound.

*There are waterfalls in the ocean. Technically the Earth's largest known waterfall lies between Greenland and Iceland — underwater. The Denmark Strait cataract is more than three times the height of Angel Falls in Venezuela, which is considered Earth’s highest aboveground uninterrupted waterfall. The Denmark Straight cataract carries almost 2,000 times the amount of water of Niagara Falls at peak flow.

*The oceans are rich with more than just marine life. Undissolved gold is in and on the seafloor. Mining for this gold — located at least a mile or two underwater and encased in rock — may not be worthwhile, as there currently isn’t a cost-effective way to mine or extract gold from the ocean. NOAA estimates that if all of the gold were extracted from the world's oceans, each person on Earth could have nine pounds of the precious metal.

*More historical artifacts lie in the ocean than in all of the world's museums combined, says National Geographic. Whether it's a Viking sundial or a jeweled gift to the ancient gods, a lot of the world's history can be found at the bottom of the seas. That's not to mention the vast number of shipwrecks lying on the ocean floor; one estimate by James Delgado, director of NOAA's Maritime Heritage Program, puts the number at one million, with the majority of the wrecks still undiscovered.

Now that you know a little more about our oceans, take time to read the Quirkles book, Underwater Utley, and learn how sea life adapts to marine habitat. On a sobering note, also conduct Underwater Utley’s Oil Spill Investigation to learn how oil spills and pollution affect sea life. Watch our video to learn more.

Watch the crystals form in the investigation!

What’s that floating in the ocean? Here’s a sobering statistic: scientists estimate more than 706 million gallons of waste oil enter the ocean every year.