Ummm. Yeah.
then again explain objects found in coal lumps of obvious manufacture;
OR 2,800,000,000 B.C. - Randian Era
ANOMALY: Klerksdorp Spherical Objects found in Africa. 
Some of the objects have a set of three parallel grooves around their equators, and some are reported to be metallic. Found in pyrophyllite in Western Transvaal, Africa. Pyrophyllite is a quite soft secondary mineral formed by sedimentation. The highly specific dating of the pyrophyllite rock layers in which these spheres are found gives an age of 2.8 billion years. The globes are claimed to have a fibrous structure on the inside with a shell around it.
These objects were found many decades ago (prior to 1980), but only recently have been reexamined. Not all are round, and none of the metallic ones have been examined. Some claim they are far younger than the surrounding material. Some testing has claimed that their balance exceeded the limit of the measuring technology - balanced to within 1/100,000ths of an inch from absolute perfection, and the only way that either nature or human technology could create them would be in zero gravity.
It should be noted that the external appearance of some spheres closely resembles images returned by the Cassini-Huygens Mission of Saturn's moon Iapetus.
It is also postulated that these could be some form of life seed. See Crick/Orgel 1973 Icarus paper (the Panspermia hypothesis) and Crick, Francis, Life Itself, 1981. These objects are dated to just before the first known appearance of life in the immediately following Proterozoic Eon.