Its climbing strata of massive limestone stones, which give it a slightly jagged look now, were originally buried by a smooth layer of fine white limestone. Scholars believe that 67,390 cubic metres of quality Tura limestone were extracted specifically for the Great Pyramid. The stone is 25% calcium carbonate (the same percentage as shell) and 75% pure oxygen, so it was certainly considered valuable at the time.
Pyramids have been built using limestone since early times. In fact, the word "pyramid" comes from an Egyptian word meaning "to cut out a piece", probably referring to the practice of cutting blocks out of a single mountain range. However, the Great Pyramid is unlike any other pyramid before or since because its builder took great care in choosing and preparing the stone. The limestone used to build the pyramid was chosen for its quality not only because of its granular texture but also due to its high content of calcium carbonate - the same component as coral reef builders use today when constructing their structures.
The Great Pyramid was undoubtedly one of the most ambitious projects ever undertaken by man. It is estimated to have taken 20,000 workers five years to complete its construction.
The limestone for the Great Pyramid's core was mined on-site at Giza, right south of the pyramid itself. It was brought to the site in buckets by men who climbed down holes cut into the rock.
The pyramid was built as a tomb for King Khufu (who took the throne around 2580 B.C.) and his family. It was designed by King's Chief Architect Imhotep, who also invented writing using hieroglyphs. According to some historians, Imhotep is said to have used quantum physics to build the pyramid.
Khufu ordered the construction of the pyramid to celebrate his victory over his two brothers who had tried to take the throne from him. The project took about 20 years to complete.
Although today it is covered with a flat asphalt roof, the Great Pyramid was originally painted red. The king probably wanted to represent himself as a living phoenix rising from the ashes - a symbol of eternal life. His people would have understood this as a sign of prosperity followed by death, but would have been impressed by the fact that he could command such enormous efforts toward fulfilling his dream.
The Great Pyramid was constructed by quarrying an estimated 2.3 million massive pieces weighing a total of 6 million tonnes. The bulk of the stones are not consistent in size or shape, and they are only loosely prepared. Mortar was used to hold the outer layers together. Local limestone from the Giza Plateau was mostly utilised. The rock is soft, and required stiffening with more resistant materials inside the structure.
The exact method of construction is unknown, but many theories have been proposed. One theory is that the structure was built by a coordinated team of workers over a period of about 70 years. Another idea is that it was built within one decade by several separate teams of builders. There is evidence that some parts of the pyramid were edited after completion, which suggests that it was not built in one single sweep. Finally, some researchers believe that the pyramid may have been built entirely by slaves.
It is known that heavy work tools such as drills, hammers, and chisels were used during its construction. Some tools that have been found at the site include ones made of copper, bronze, iron, and limestone. It is believed that these tools were used by different groups of people to perform specific tasks.
The Great Pyramid was probably not built alone. It is thought that there might have been other structures at Giza at the time, including small temples, granaries, and tombs.
Over 2 million pieces of rough yellow limestone were extracted from the earth on-site to build the tallest pyramids. The majority of the blocks were dug into the earth and then extracted with wooden levers. They utilized enormous wooden sleds that they hauled across damp sand to transfer the heavy stone. Some believe they were used as burial tombs for Pharaohs.
The pyramids were originally painted black, but over time they have turned white due to exposure to wind and rain. They stand about 30 feet high and range in size from around 25 yards on a side to just under 10 acres for the smallest one.
Amazingly, no one is exactly sure who built the pyramids. Some scholars believe they were built by slaves, while others think they were constructed by free men hired by the Pharaohs. However, what we do know for certain is that the pyramids were built between 250 B.C. and 664 A.D., which makes them much older than anyone else's work at the time. They remained standing until the 11th century A.D when an earthquake destroyed two of them. It is believed that many more ancient structures remains undiscovered due to soil instability caused by flooding from the Nile River.
In addition to being works of engineering art, the pyramids were also religious monuments for Pharaohs to pray to their gods after death.
Giza's Pyramids contain almost 5 million chunks of limestone. They were once thought to be sculpted stones. According to new evidence, they were made of agglomerated limestone concrete. Prof.'s freshly revised book reveals the scientific underpinning, including analysis, formula, and stone production. He also answers questions about this groundbreaking discovery that has changed how we view ancient monuments.