Earflare, Condor

Silver, gold, gilded copper, shell

Peru. Moche. 390 to 450 AD

Moche metalworkers were among the most inventive and talented in ancient Peru. They developed sophisticated mechanical and metallurgical techniques for joining the three basic metals they worked: gold, copper, and silver. On these technically complex earflares, the front plates are made of sheet gold to which repoussé silver birds are attached by small tabs. The back plates and shafts are of gilded copper and also join in this manner. The ornaments were worn in the distended lobes of the ears, the long tubular shafts counterbalancing the weight of the frontals.

The birds with massive talons and strong, curved beaks adorning these earflares depict Andean condors, identified by the large caruncle (fleshy protuberance) at the base of their beaks and the wattle around their necks. Impressive birds with a wing span of up to ten feet, Andean condors inhabit the high Andes mountains above 9,000 feet. They are primarily carrion eaters, but will occasionally kill for food. Condors and vultures are highly symbolic birds and are a frequent theme in Moche art. They embellish tumis, or knives used in ritual sacrifice, and are often shown pecking at human and animal heads and bodies. Because of their eating habits, they have a natural connection with predation, death, and sacrifice. Perhaps these ornaments were worn by an individual performing a sacrifice.

The Met

In preparation for an outgoing loan, the Outer Sarcophagus of the Royal Prince, Count of Thebes, Pa-seba-khai-en-ipet came to the conservation lab for examination, documentation and treatment. In addition to deciding how best to stabilize the coffin for travel, conservators took the opportunity to learn more about how this object was made and how it changed over time.

The substrate of this coffin is made from many pieces of wood joined together. Because indigenous trees capable of producing timber were relatively scarce in ancient Egypt, Egyptian carpenters developed techniques that helped them to be efficient with their resources. Woodworkers often mixed pieces of lower grade timber with domestic or imported higher quality wood, and they used a wide variety of joining techniques to cobble the pieces together.

The wood was shaped using various tools, including saws, adzes, chisels and drills. To prepare the wood surface for decoration, joins were often covered with textile patches or other preparation layers. On Pa-seba-khai-en-ipet’s coffin, textile patches are visible in some areas where the surface decoration has been lost, and some areas have been modeled using a putty made from clay, gypsum and calcite.

The surface decoration of Pa-seba-khai-en-ipet’s coffin was done by first applying a white ground layer (these were often made from gypsum mixed with animal glue) and then painting using mineral pigments mixed with a plant or animal-based binding medium (ie. gum Arabic or animal glue). Paints were probably applied using reed pens or brushes made from plant materials, and sometimes low relief was created with Egyptian blue, a pigment made by combining a copper source with calcite, sand and an alkali flux and heating this mixture to a high temperature. Additionally, coffin surfaces—particularly during some periods of Egyptian history—were often coated with a varnish layer. The varnish on Pa-seba-khai-en-ipet’s coffin is made from tree resin.

In order to learn more about these techniques I attended a workshop and conference at the Fitzwilliam Museum at Cambridge University titled Ancient Egyptian Coffins: Past, Present, Future. During the three-day workshop, participants learned all about the raw materials of coffin production and we got to try many of these techniques ourselves. It was definitely a challenge! One of the great things about this type of experimentation is that it gets us to think like craftspeople, and it can help inform the questions we ask when examining the objects in our collection.  

Posted by Anna Serotta 

This is how friction principles work for welding of pipe. There are several friction welding techniques which are being utilized in manufacturing/construction industries, to join several range of materials. 

Friction welding is categorized by working principle of equipment and materials to be joined. Types of Friction Welding involves 

Spin Friction Welding

Linear Friction Welding

Friction Surfacing

Vibration Friction

Orbital Friction Welding

These types are different from each other on the basis of movement of equipment and material (pipe, plate) to be joined. Moreover there is another technique which is a popular joining technique to produce high quality and strong weld joints. 

Friction Stir Welding:

In this type, a tool is allowed to move along the joint line, making the joint material soft and fused by its rotational movement. A constant pressure is applied on the lateral sides of material (pipe or plate pieces) until the joint gets fully fused. 

Friction stir welding has some advantageous features over arc welding process. It requires no, gas shield, no post weld heat treatment and no additional filler metal. FSW also produces quality welds in wide range of non-ferrous materials.