Have kept a file of general definitions for my associations, might not be good for somebody else (recently updated them making a few small changes). Here are the most important definitions, some are only a color sample from the object. Gold and silver were blue/orange, now only the natural color.
[FONT=Verdana,Arial,Tahoma,Calibri,Geneva,sans-serif]Gold coin colored markings (circles, rectangles, lines, arrows) for gold treasure or gold coins, bullion, nuggets.
Silver coin colored markings (circles, rectangles, lines, arrows) for silver treasure or silver coins, bullion, nuggets.
Platinum colored markings (circles, rectangles, lines, arrows) for platinum treasure or native platinum and nuggets.
Bronze color for bronze artifacts or coins.
Copper color for native copper deposits or copper artifacts, coins.
Yellow line box (or solid filled circles) for gold veins and deep alluvial placer deposits.
Yellow outline circles for shallow alluvial gold placer deposits.
Red outline circles for places to check metal detecting, for mostly loose coins/treasure or artifacts of value, from surface down to 1-2 feet deep.
Red line box (or solid filled circles) for very deep coins/treasure or artifacts of value.
Purple color for ancient religious sites or tombs, temples, and other ancient burial grounds.
White in general is a color indicator, I use for natural caves or man made tunnel entrances and mine shafts, other similar type excavations (including old wells, tombs, etc.).
Lilac colored line box (or solid filled circles) for rough (uncut) crystals and gemstones, jewels (cut, polished or faceted), pearls.
Green in general is a color indicator, I use for various other targets mostly archaeological (old ruins or foundations but especially those non-metallic objects such as Indian flints, glass, pottery, carved stone with treasure signs).
Black is used to show danger, death traps, explosive devices, bombs, or live ammunition.
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