White crystals can be found in many forms both naturally occurring and man-made. There are a variety of uses for white crystals depending on their composition and structure. Some of the most common white crystals include salt, sugar, quartz, and certain synthetic polymers. Each type of white crystal has unique properties that make them useful for different applications.
Salt
Salt or sodium chloride is one of the most abundant naturally occurring white crystals. It forms in cubic crystals and can be found in seas, lakes, and underground salt deposits. Salt has been an essential part of human civilization going back to ancient times.
Some uses of salt include:
| Seasoning | Salt enhances flavor and acts as a preservative for foods. It is used universally in cooking and food preparation. |
| Food preservation | Salt pulls water out of foods through osmosis, preventing bacterial growth. Salting is one of the oldest ways to preserve meat, fish, vegetables, and cheeses. |
| Water softening | Hard water contains minerals like calcium and magnesium. Salt ions exchange with the mineral ions, effectively softening the water. |
| De-icing | Salt lowers the freezing point of water leading to ice melting. It is spread on roads and sidewalks to melt snow and ice. |
| Chemical manufacturing | Salt is broken down to produce chlorine, sodium hydroxide, and other chemicals for industrial processes. |
| Tanning and dyeing | Salt is used in leather tanning to remove hair and fat. It also helps bind dye to fabrics in the dyeing process. |
Salt has been a strategically important resource throughout history. Entire wars have been fought over control of salt. The word “salary” even comes from the Latin word “salarium” referring to the money paid to Roman soldiers to buy salt.
Sugar
Sugar is a broad term used for various sweet-tasting carbohydrates like sucrose, fructose, and glucose. The most common sugar is sucrose which comes from sugarcane or sugar beets. It appears in crystalline form as white sugar.
Some common uses of granulated white sugar include:
| Baking | Sugar is used extensively in baking to sweeten and influence texture in items like cookies, cakes, pastries, and doughs. |
| Preserving | The high sugar concentration of jams, jellies, and preserved fruits creates an environment inhibiting microbial growth. |
| Candy | Crystalline sugars like sucrose and glucose are essential ingredients in nearly all types of candy and chocolate. |
| Beverages | Sugar sweetens coffee, tea, juices, sodas and is fermented to make alcoholic drinks like rum, beer, and wine. |
| Sweetener | Table sugar substitutes for other sweeteners like honey and maple syrup as a basic sweetening agent. |
| Food processing | Sugar acts as a preservative, bulking agent, coloring agent, and flavor enhancer in processed foods. |
Like salt, sugar was also an historically important commodity stimulating global trade and exploitation of slavery for sugarcane plantations. Today, it remains a widely produced crop and food ingredient.
Quartz
Quartz is one of the most common minerals on Earth made up of silicon and oxygen. It forms in six-sided prismatic crystals and aggregates containing individual crystals. Quartz is identified by its hardness, luster, and glass-like transparency. Some varieties include rock crystal, amethyst, citrine, milky quartz, and smoky quartz.
Some uses of quartz crystals include:
| Electronics | Quartz crystals oscillate at precise frequencies dependent on their cut and size. This makes them ideal for use as frequency controllers and timers for radios, watches, and computing devices. |
| Optics | High purity quartz transmits light well across the UV, visible, and near infrared ranges. It is used for lenses, prisms, and optical fibers. |
| Abrasives | The hardness of quartz makes it useful as an abrasive for grinding, polishing, sandblasting, and cutting. |
| Jewelry | Varieties of quartz like amethyst and citrine are used as gemstones in jewelry. The crystalline structure enhances light reflection and sparkle. |
| Labware | Quartz glassware is needed for high temperature lab processes and viewing UV light. It has low thermal expansion and high chemical resistance. |
| Building materials | Sands and aggregates containing quartz are ingredients in concrete, mortar, stucco, road construction, and landscaping. |
Natural quartz crystals have intrigued people since ancient times and remain an integral mineral contributing to modern technology.
Synthetic Polymers
Many plastics and synthetic fibers are made up of long chain polymer molecules formed from repeating units called monomers. Common white crystalline polymer materials include polyethylene, polypropylene, nylon, and polyester.
Some uses of synthetic white polymer crystals include:
| Plastic packaging | Polyethylene and polypropylene are made into plastic bags, containers, bottles, wraps, and other packaging. |
| Plastic parts | The versatility of plastics allows molding into gears, cases, handles, machine parts, and consumer products. |
| Textiles | Nylon and polyester can be spun into synthetic fibers for clothing, upholstery, ropes, and other textile products. |
| Appliances | White polymer materials have properties like low friction, heat resistance, and electrical insulation that make them useful in appliances. |
| Vehicles | Polymer crystals are machined intodashboards, batteries, bumpers, shells, and other automotive parts. |
| Construction | Polymer insulation, wallboards, sealants, paints, barriers, and piping are common in construction. |
Synthetic polymers only entered mass production in the 20th century but are now ubiquitous and keep finding new applications with over 200 million tons produced annually.
Analysis of Composition and Structure
The useful properties of white crystals come from their molecular and crystalline structure. Some patterns emerge when analyzing and comparing their composition:
| Salt | Ionic crystal made of alternating sodium cations and chloride anions in a cubic structure. |
| Sugar | Molecular crystal with a saccharide composition like sucrose, glucose etc. forming monoclinic crystals. |
| Quartz | Silicon dioxide crystal with silicon and oxygen in continuous framework structure and hexagonal symmetry. |
| Synthetic Polymers | Crystalline structure of long repeating chain molecules like ethylene or PET plastic. |
The geometry and strength of atomic/molecular bonds in these crystalline solids determine macroscale physical properties like hardness, melting point, solubility, electrical and optical behaviors. Materials scientists can engineer new crystals with desired properties by altering composition and atomic structure.
Occurrence in Nature and Manufacturing
White crystals originate from both natural and synthetic sources. Geological processes concentrate natural white crystals, while industrial processes manufacture synthetic versions:
| Salt | Mined from ancient dried seabeds and salt lakes or extracted from seawater. |
| Sugar | Extracted and concentrated from sugarcane and sugar beets. |
| Quartz | Formed through geological processes like sedimentation and hydrothermal vents. |
| Synthetic Polymers | Produced through polymerization of hydrocarbon monomers into long chains. |
Manufacturing allows large-scale production of synthesized versions of white crystals like sugar and polymers. Natural formations still produce the majority of crystals like salt and quartz.
Everyday Applications
White crystals find utilization in countless everyday applications across industries like:
| Food industry | Salt, sugar, synthetic emulsifiers and stabilizers. |
| Clothing industry | Nylon and polyester fibers. |
| Construction industry | Quartz aggregates, polymer sealants. |
| Consumer goods | Packaging plastics, silicone, electronics. |
| Automotive industry | Tires, plastic components, paints. |
| Appliances | Plastics, silicone, electronics. |
Their unique structures impart useful properties like hardness, electrical insulation, heat resistance, and chemical stability. Continuing research discovers new potential uses for known and novel crystalline materials.
