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The product keyword refers to both calcium carbonate and limestone. These two types are distinct yet related. They share some similarities, but they also serve various purposes. As such, they are often considered separately based on their different compositions and uses.
Copper Mountain
This is calcium carbonate which is a naturally occurring mineral found in sedimentary rocks, such as limestone. It is composed of calcium, carbon, and oxygen (CaCO3). It is often mined from quarries and used in various industries.
Limestone
Like calcium carbonate, limestone is a sedimentary rock primarily composed of calcite. Calcite is a crystal form of calcium carbonate. Lime comes in two primary forms (quick lime and slaked lime) which is produced by heating limestone in a kiln. This process decomposes the rock, releasing carbon dioxide. The result is a highly alkaline powder known as quicklime or hydrated lime when mixed with water). Quicklime is used in steel production, water treatment, and as a soil stabilizer in construction.
Marble
Marble is a metamorphic rock formed from limestone under heat and pressure. Marble is composed of calcium carbonate in a crystalline form. It is widely used in construction, particularly in the manufacture of marble slabs and tiles for countertops, flooring, and architectural accents.
Oyster Shells
Oyster shells are also a valuable source of calcium carbonate. They are a sustainable alternative to mined sources. High in natural calcium carbonate, they are crushed and used in agriculture to amend soil acidity. They are also used in livestock feed to provide essential calcium for eggs and bone development.
Calcitic vs. Aragonitic
Calcium carbonate exists in two crystalline forms: calcite and aragonite. Calcite is the purer, more stable form found in sedimentary rocks like limestone. Aragonite, found in coral and mollusk shells, is less stable and converts to calcite over time. Both forms are important in different industrial applications due to their varying crystal structures.
Historical Uses of Limestone
Limstone has been used since the ancient times for building materials such as the great pyramids of Egypt and medieval castles in Europe. It is also used for lime which is used in cement and mortar, key components in construction. The natural acidity of limestone rich soils has made them historically ideal for vineyards and other agricultural practices.
High Purity and Brightness
Calcium carbonate powder especially that which is sourced from marble, is highly pure, with minimal impurities. This high purity results in a brilliant white color (or brightness), which is critical for applications like paint, paper, and plastic where color and opacity are important. Limestone used in construction may not be as pure and is often grey or off-white due to impurities like clay, sand, or iron.
Versatility
Calcium carbonate and limestone are two highly versatile materials. Calcium carbonate is used in food and pharmaceuticals as a calcium supplement, antacid, and in carbonated drinks. Limestone is primarily used in construction for cement, concrete, and as an aggregate in road building. Both are important in steel and glass manufacturing as well.
Finely Grinded Limestone
Limestone can be grinded into a fine powder known as calcite or whiting. Whiting is a clayey limestone that has been grinded and washed for use in the manufacture of putty, plaster, and paints. Calcite, on the other hand, is a highly pure powder used in paint, rubber, and plastics for its brightness and texture.
Limestone’s Carbon Sink Role
Limestone plays an important environmental role as a carbon sink. When carbon dioxide in the atmosphere mixes with water, it forms weak carbonic acid. This acid then erodes limestone rocks, releasing calcium ions into rivers and oceans. These ions eventually form limestone sedimentary rocks. This process naturally removes carbon dioxide from the atmosphere, mitigating the impact of greenhouse gases on climate change.
Calcium Carbonate in Health and Industry
Calcium carbonate is widely used in the pharmaceutical industry, particularly as a calcium supplement for bone health. It is also used in antacids to neutralize stomach acidity. In the food industry, it acts as a antacid and as a carbonation source in foods like noodles. Paper, plastic, and paint industries use it as a filler and pigment due to its fine texture and bright color.
Storage Conditions
Calcium carbonate and limestone powder should be kept in a cool, dry place away from direct sunlight. The ideal temperature is room temperature (15-25°C or 59-77°F). Humidity and exposure to air can cause the powder to clump or degrade. This is why it is important to keep the powder in an airtight container to increase its shelf life.
Packing
Calcium carbonate and limestone powder usually come in sealed plastic or metal containers. They may also come in plastic or woven bags for larger quantities. Each container should be labelled with both the manufacturing date and expiration date. Buyers should also store the products in their original containers and repack them securely.
Use of FIFO System
FIFO is short for first in, first out. It is the ideal storage practice for calcium carbonate and limestone powder. This allows the older stock to be used before the newer stock to ensure product quality and effectiveness over time.
Visual Inspections
Users must inspect the powders visually before use. Look out for any signs of clumping, discoloration, or unusual odors. Any signs of moisture or pest contamination means the product has been expired and must not be used at all.
Calcium Carbonate
Calcium carbonate supplements should ideally be stored in an airtight container to protect them from moisture and oxygen. This extends their shelf life significantly. When stored properly at room temperature, calcium carbonate supplements typically remain stable for 2-3 years. However, it’s important to check the expiration date on the packaging and ensure the product is not discolored or has a strange odor before use.
Limestone
Limestone powder used for agricultural or industrial purposes can last indefinitely if kept dry and free from contaminants. Unlike supplements, practical application limestone powder should be checked regularly for purity and consistency. Look out for any signs of clumping or moisture content.
Assess the Purity
Buyers should look for high-purity calcium carbonate, with a minimum purity level of 95% for industrial uses. If the calcium carbonate is intended for food or pharmaceutical use, go for ultra high purity (99% or above). Suppliers of quarrying limestone should provide assay reports to verify the mineral content and purity.
Consider the Particle Size
The intended application determines the particle size for calcium carbonate and limestone. Industrial grades have coarser particles suitable for construction or steel making. Paper, rubber, plastics, and paint industries prefer finely grinded powders that improve texture and color. Buyers should request particle size distribution data from suppliers to ensure compatibility with their processing requirements.
Assess Their Source
Sourcing plays an important role in the quality and sustainability of calcium carbonate and limestone. Buyers should consider the environmental practices of the quarrying and mining operations. Logo for suppliers who have responsible eco-friendly practices. They should also provide detailed documentation on their product’s chemical composition and absence of harmful impurities like heavy metals.
Assess the Consistency
Consistent particle size and purity are important for applications that require uniform results. Like in paint or plastic manufacturing for instance. Variability in calcium carbonate or limestone quality affects product performance and disrupts production processes. Buyers should work with reputable suppliers who have quality control procedures. This ensures the same material is delivered consistently with every order.
Transportation and Cost
Cost of transportation plays a big role in the overall calcium carbonate and limestone procurement cost because they are bulky and bulky. Buyers located far from their suppliers will incur high shipping costs, thereby increasing the overall cost. Evaluate logistics and shipping costs by comparing various suppliers. Sometimes, suppliers offer free shipment to certain locations which can offset the high cost.
Calcium carbonate has a long shelf life if it is stored in cool dry airtight containers, away from sunlight. It can last for 2-3 years or even indefinitely. Expiration can occur if moisture, air, or contaminants get into the container.
Calcium is a chemical element with the symbol Ca. Calcium carbonate on the other hand is a compound that contains both calcium and carbon. It is often used as a dietary supplement for bone health. It is also used in antacids, and as a calcium source in foods and animal feeds.
Not all calcium carbonate is food grade. Food grade calcium carbonate must meet strict purity standards to ensure it is safe for consumption. These standards include tests for heavy metal contamination and other harmful impurities. To be sure purchases, buyers should look for calcium carbonate labelled “USP” or “food grade.” This indicates it meets the FDA standards for supplements and food additives.
Calcium carbonate is a versatile compound found in various forms. It is found in limestone, marble, and seashells. Chalk on the other hand is a soft, porous sedimentary rock primarily made up of marine-origin calcium carbonate. It is usually white in color and was formed from microscopic organisms deposited on the ocean floor.
