Transition elements involved

Move your mouse over the names of the metals below to see where they have been used on the orb and cross.

	copper gold cobalt	iron chromium manganese molybdenum nickel

Using the transition metals in the Orb and Cross

The transition metals have many important and useful characteristics in common. However, it is the individual variations in the properties of these metals, which contribute to their specific importance and uses. This leads to their widespread appearance in all types of structures.

In the reconstruction of the Orb and Cross for the Frauenkirche, it is possible to see some excellent examples of their varied applications and versatility.

Gold
	can be hammered into extremely thin sheets to cover other surfaces
	it resists corrosion, being very low in the reactivity series
	it has highly reflective surfaces, important in this situation where it has to be seen from a long way off
	originally the gold was applied using a process involving mercury, although this was effective, the mercury is poisonous, so it was not used in the reconstruction

 

Copper
	copper is a malleable metal suitable for shaping
	the Orb was made from two single sheets of metal, hammered into shape
	it was suitable too for the intricate shaping of the clouds and rays
	it is resistant to corrosion but needed some coating for prolonged exposure, before covering with gold leaf

 

Cobalt
	a cobalt compound is used to give the colour of the clouds
	transition metal compounds are often coloured and are used in the majority of pigments, for this reason

 

Surgical steel
	surgical steel is used for making the main axes of the Cross
	iron, chromium, nickel, manganese and molybdenum are the main metallic constituents of the steel, it also contains carbon
	it must be strong and corrosion proof
	at 96 metres above the ground it must require minimal repair and must not break
	chromium, nickel and molybdenum provide corrosion resistance and together with the other the other components, give the strength required to overcome factors such as wind strength at this height
	originally iron was used for these parts, but it is far less resistant to corrosion and lacks strength