• PHANEROZOIC0 to 542 ma 
      • CENOZOIC0 to 65.5 ma 
        • QUATERNARY0 to 2.588 ma 
        • NEOGENE2.588 to 23.3 ma 
        • PALEOGENE23.3 to 65.5 ma 
      • MESOZOIC65.5 to 251 ma 
        • CRETACEOUS65.5 to 145.5 ma 
        • JURASSIC145.5 to 199.6 ma 
        • TRIASSIC199.6 to 251 ma 
      • PALEOZOIC251 to 542 ma 
        • PERMIAN251 to 299 ma 
        • CARBONIFEROUS299 to 359 ma 
        • DEVONIAN359.2 to 416 ma 
        • SILURIAN416 to 443.7 ma 
        • ORDOVICIAN443.7 to 488.3 ma 
        • CAMBRIAN488.3 to 542 ma 
    • PRECAMBRIAN542 to 4600 ma 
      • PROTEROZOIC542 to 2500 ma 
      • ARCHEAN2500 to 4000 ma 
      • HADEAN4000 to 4600 ma 


Moon map

The map feature allows you to view the distribution of rocks on a map of the Earth (Moon view is currently unavailable due to a technical issue). Individual rock samples appear as a red 'location pin', but where pins are too close to show, a numbered circle indicates multiple pins in a small area. Simply zoom into the area of interest and click a pin to display the flag and a small image of the rock. Clicking the name opens the individual rock page with all the information about that rock.

The age of each rock is key to understanding the context of rocks and their evolution. For example, the oldest metamorphic rocks are high grade gneisses in northern Scotland, whereas most of the sedimentary rocks are Paleozoic and more recent. Searching 'in Time' allows you to group different rock types by geologic age. The default shows only the highest level timescale; the different periods can be revealed by clicking the plus (+) icon, and the rocks for each period are revealed by clicking the arrow to the right.

The 'in Focus' search allows you to search for any term that appears in the metadata or in the text describing the rock. The open title and description boxes at the top allow you to input any term. Thus a search for 'basalt' will yield basalts in any collection, and a search for 'biotite' will reveal all rocks containing biotite. The same search can be performed by selecting biotite in the rock-forming minerals box, or by selecting basalt in the category box. The number of returns for a free text search can also be reduced by selecting more than one of the criteria; for example, selecting 'quartz' and 'igneous' yields all quartz-bearing igneous rocks.