Marks and symbols are indeed very helpful in locating hidden objects; and considered as one of the most important "tool" by most treasure hunters. While it is true that it is one of the requirements for a succesful treasure retrieval, it is also true that these "markers" are used by some unscrupulous person to entice unsuspecting treasure hunters. Basing the markers and symbols circulating in treasure world, these "artist" can make curvings on stones to assimilate true treasure markers. Though these people are not involve in selling fake gold bars, they also fall in the category of con artist, thus ripping money from other by deceitful means.
It is also my opinion, that these markers are exstremely helpful 40 years ago, but at present times (except for untouched and virgin sites), these markers became unusable, due to the fact that untrained treasure hunters had moved, removed, and damaged these markers from its original position and locations. Let us also consider some areas where markers seems undisturbed, but the hidden object has been recovered years back by knowledgable hunters, lucky hunters, by relatives of Japanese soldiers, and the least are the soldiers themselves who returned back to Phil. after the war.
These are some of the loopholes that faces by the newbie hunters; plus the rich imaginations that give images to any natural objects found in the vicinity of suspected treasure sites.
I wrote this subject not to weaken the enthusiasm, but to serve as a precautionary measures before a hunter spill his hard earned money in treasure hunting.