B.1 Geological Setting
Located within the Pacific Rim of Fire, the Philippine archipelago is hypothesized as having been formed 43 million years ago. Its 7,109 islands rest on top of underwater mountains formed by the outpourings of molten rocks from the earth's interior, thus creating an ideal setting for mineral deposition. (After Wolfe, J.A., "Origin of the Philippines by Accumulation of Allochthons" in The Philippine Geologist July- September 1983 Issue, p.17)
In the archipelago, resurgent volcanoes particularly provided access for rising gold-bearing solutions which cool to the geotherm of 300 degrees Celsius at about 400 m depth. At this point, the gold began to precipitate and epithermal gold deposits were formed over geologic time of 1.5 million years from the present time. (After Wolfe, J. A., in International Mineral Development Sourcebook, 1993)
B.2 Mineral Resource Base/Reserves and Estimated Values
The government's mineral resource data (1973-1996) could account only for about 10% of the country's total mineral wealth. Nevertheless, the Mines and Geo-Sciences Bureau (MGB) is continuously updating and upgrading the country 's mineral estimates especially, the metallic sector: 1) iron (iron ore); 2) iron alloys (e.g. chromite, nickel, molybdenum, manganese ore, cobalt); 3) base metals (e.g. copper, lead, zinc, mercury or quicksilver, cadmium); 4) light metals (e.g. aluminum or bauxite, manganese); 5) precious metals (e.g. gold, silver, platinum); and 6) rare metals (e.g. uranium). (Table 1)
The MGB is also updating and upgrading its estimates of the country 's industrial materials or non-metals, of which 38 are now listed. (Table 2)
As for the primary energy sources, the nationís coal, petroleum and natural gas endowments can be further explored and their potentials further assessed for long-term domestic utilization. Their exploration, development and exploitation however fall under the present mandate and competence of another government agency, the Department of Energy (DOE). (Table 3)
Recently, the government came out with pronounce- ments that the estimated mineral wealth under Philip- pine soil is $800 billion to $1 trillion. (The NEDA chief had posted the total value at $840 billion.) Arriving at this estimate would be a very difficult accounting process. But this kind of inventory is necessary and logical in view of the governmentís plan to revitalize the mining industry. This estimation would have been guided by the environmental and natural resource accounting (ENRA) system developed in the 1990s.
In order to check the governmentís $800 billion to $1 trillion price tag of Philippine mineral resources, a very rough attempt was made to list these mineral assets and to compute for their present worth based on available market data. But this was done with a caveat: the monetary figures are only indicative, partial and preliminary.
At 10% potential, the combined worth of listed Philippine mineral resources amounts to $2.1 trillion. (Table 4) The 12 listed metallic minerals have a total value of nearly $465 billion. Twenty-five recorded non- metallic or industrial minerals would fetch at least $71.7 billion. The three mineral energy resources amount $1.5 trillion. Quantitative details are found in Tables 1, 2, 3 and 4, respectively.
If and when the total cost of extracting, processing and marketing of these minerals would amount to 50% of the total mineral worth of $2.1 trillion, a theoretical gross profit of at least $1.05 trillion would accrue to the coffers of the nation.
Added value generated by subjecting mineral-based materials to the semi-fabrication and fabrication stages would perhaps be twice that of the theoretical gross profit [$1.05 trillion x 2 = $2.1 trillion]. If the combined cost incurred in semi-fabrication and fabrication would amount to 33% of the added value, a profit margin of at least $1.4 trillion would accrue again to the nationís coffers.
Should the bulk of the nationís debts (at least $52.5 billion) be settled by the revenues generated from the disposition of mineral-based products, there would remain a very substantial portion of the theoretical gross profit ($997.5 billion) available for defraying the long-term cost of national development.
And as a happy postscript, this would be augmented by the $1.4 trillion profit retained intact that was obtained from the value-adding operation.
But to reiterate, the foregoing computation is just a conjecture. It is a heuristic attempt at the tremendous economic potential of the countryís mineral resources, and its redeeming power to overturn the economic plight of the Filipino people.
B.3 Mineral Prospects
The London-based 1991 Annual Mining Review, Mining Journal featured the countryís mineral wealth. Based on how much a mining company can mine in a one square kilometer land area, the Philippines ranked 2nd in gold worldwide; 3rd in copper; and 6th in chromite. (After Corpuz, Catalino in Christian Aid & PIPLinks  report). Its write-up on the country ís gold prospect confirmed the findings of a UNDP study in 1984 that ranked the Philippines second to South Africa in terms of gold endowment per square kilometer (BMG/UNDP/UNDTCD Project Document PHI/85/001).
In 1997, a technical report the United Nations Industrial Development Organization (UNIDO) cited the strategic economic value of the gold ore at Mt. Diwalwal as one that is still easily accessible and that contains the gold metal in concentration from 25 up to 100 grams per ton, approximately 25-50 times more than the famous gold ore from the Witwatersrand Basin in the Republic of South Africa (UNIDO Project Document XX/PHI/97/XXX).
While gold deposits are found throughout the country, they are concentrated in the five (5) recognized gold mining districts: 1) Baguio gold district; 2) Paracale gold district; 3) Masbate gold district; 4) Surigao gold district; and 5) Masara (Davao) gold district.
The Mines and Geo-Sciences Bureau in 1986 placed the country ís gold ore estimated reserves at 2,108,260,000 metric tons that have an average grade of 2.4 gm Au/Mt. (Table 1)
The gold metal recovered from the gold ore reserves would be about 162.6 million troy oz (5.2 million tons). Estimated value of the yellow metal is $73.4 billion.
Usually associated with those of gold, silver deposits have an average silver to gold ratio of 2:1 based on ore assays and production figures of Philippine primary gold mines.
The silver metal recovered from the above gold ore reserves would be about 325.3 million troy oz (10.4 million tons). Estimated worth of this precious metal is $2.4 billion.
Copper deposits are also widely distributed throughout the country, and most copper deposits contain variable amounts of gold and silver. Thus, the countryís copper mines have been contributing a substantial portion of the overall Philippine gold production.
Estimated reserves of the copper ore in 1996 amounted to 4,052,087,000 metric tons that have an average grade of 0.4% Cu. (Table 1) Assessed value of the base metal stands at $55.7 billion.
Chromite deposits occur along the eastern and western belts of the archipelago, and in northern Mindanao. Also known as iron chromium oxide, chromite is the most important chromium ore.
In 1986, chromite reserves measured 91,576,000 metric tons and their grades range from 21.3% Cr to 43.5 % Cr. (Table 1) Assessed worth of the metal is pegged at $1.4 billion.
Nickel deposits, mainly in the form of nickeliferous laterite, also occur along the eastern and western margins of the archipelago and in northeastern Mindanao. In the 1970s, the country was believed to have the biggest nickel reserves in the world.
In 1986, nickel reserves totaled 1,569,870,000 metric tons with an average grade of 1.1% Ni. (Table 1) With an estimated value of $229.3 billion, this makes nickel theoretically the countryís top ranking metallic mineral resource.
In 1997, a survey of major mining firms operating in the Asia-Pacific ranked the Philippines (despite its relatively small land area) second only to Indonesia in terms of geological prospectivity. It should be noted that Indonesiaís total land area measures about 1,919,400 sq km, while that of the Philippines is only 300,000 sq km (or 30 million hectares). Geologists at the Mines and Geosciences Bureau estimate that the potential minerals (e.g. copper, gold, chromite and nickel) onshore cover an area of about 90,000 sq km (or 9 million ha).
The survey ís accompanying mineral development forecast was that for the period 1995-2015, the Philippines would develop a minimum number of 11 new deposits and a maximum of 30 new deposits. Its bottomline however was that, in all probability, at least one new mine per year would be developed Ė for an end-total of 20 new mines. Out of that probable total number, 11 mines would be medium- to large- scale epithermal gold deposits, while five mines would be copper-gold deposits. The remaining four mines would be either chromium or nickel mineral finds. (After Clark, Allen L. in Globalizing Philippine Mining  IBON)
According to the Director of the Mines and Geosciences Bureau, the new major gold deposits are:
Bulawan under Philex Mining began gold production in 1996 as the first large-scale gold mine developed since the passage of the Mining Act. Longos contains the highest grade of 11.1 gm Au/Mt.
The new major copper-gold deposits are: