A shield with an eagle in the center
The rank typically associated with the gold leaf insignia in the army is that of a Major.
Although there are different types of military badges for the US Army, there are no subdivisions for military insignia. The total number of military insignia for the US Army is 57.
For the US Army, it's a bronze oak leaf. The same insignia is used by Majors in the Air Force and Marine Corps, and by those holding the rank of Lieutenant Commander in the Navy and Coast Guard while wearing certain uniforms.
The hat insignia and rank insignia contain the eagle from the great seal
There are a bunch of them. Branch of Service insignia, rank insignia and other insignia that aren't unit-specific are found in Army Regulation 670-1, which is downloadable from a few places. Distinguished Unit Insignia, which everyone calls unit crests, and patches are not in that reg; check the Institute of Heraldry website at http://www.tioh.hqda.pentagon.mil/
Lieutenant Colonel insignia is identified by a Silver Maple Leaf. In the US Army it is a cluster of silver OAK leaves. In the British army it is a crown and a single 'pip'.
On the left lapel of the wearer.
Yes, they do, except for the Army Combat Uniform, which does not have epaulets.
Howard Chandler Christy
staff specialist
On 18 June 1780.
March of 1955.