Goldcorp (GG) is one of the largest gold miners in the world. Last year it produced nearly 2.9 million ounces of gold from several major mining complexes. While the company expects that output to slip to 2.5 million ounces this year, that doesn't mean it's running low on gold. Quite the contrary since it holds a whopping 41.8 million ounces in reserve. That's an unbelievably valuable resource for the $14 billion gold company, worth an astounding $55 billion at current gold prices.

That said, the company expects to increase its stockpile significantly over the next few years, with its goal to end 2021 with 50 million ounces in reserve even as it increases output. Here's a closer look at the company's mammoth pot of gold and how it intends on growing it in the future.

Gold nuggets with a pick on top.

Image source: Getty Images.

Digging into Goldcorp's gold reserves

Goldcorp owns stakes in several mining complexes across North America and South America. However, the cornerstone of the company's portfolio is its wholly owned Peñasquito mine in Mexico, which is the largest gold producer in that country. According to Goldcorp's estimates, that mine holds 9.9 million ounces of proved and probable reserves. In addition to that, the mine also produces silver, lead, and zinc.

The company's next largest source of gold is the Pueblo Viejo mine in the Dominican Republic, which is one of the biggest gold mines in the world. Goldcorp holds a 40% stake in this mine, with Barrick Gold (GOLD 1.68%) holding the other 60%. That said, given the mine's massive size, that minority stake gives the company a large prize of 5.4 million ounces of gold reserves.

Another major source of reserves is the El Morro – NuevaUnion project that it co-owns with Teck Resources (TECK 1.10%). The company's 50% stake in that project gives it an equal share in the mine's reserves, with Goldcorp's claim currently totaling 4.5 million ounces.

Finally, two other large contributors to the company's reserves are the wholly owned Cerro Negro and Eleonore mines, which hold 4.9 million and 4.6 million ounces of reserves respectively. The Cerro Negro mine in Argentina is one of Goldcorp's newest mines while Eleonore is the company's latest mine in Canada.

Gold panning tools full of gold, sitting on the edge of a body of water..

Image source: Getty Images.

How Goldcorp plans to grow production and reserves without skipping a beat

Goldcorp's gold reserves imply that the company can keep producing at its current rate for nearly 17 years. Though, the company's current plan is to accelerate its pace of production so that it will increase output to 3 million by 2021, which is 20% higher than 2017's expected production level. Further, the company plans to deliver that increased output rate -- which equates to 13.7 million ounces of production over the next five years -- while growing its gold reserves to 50 million ounces by 2021, or 20% higher than its current level.

The company plans to achieve that ambitious aim via organic exploration and development of its portfolio. One such project is at its Porcupine mine in Ontario, which is one of the longest-running operating mines in North America, having produced for 107 straight years. While producers have pulled out more than 67 million ounces from the mining camp over that time frame, Goldcorp believes there's still plenty left. According to the company's estimates, Porcupine has 2.3 million ounces in reserves. Further, through years of exploration, the company believes there are another 8.5 million ounces of measured and indicated resources farther underground. That's why Goldcorp is currently studying the development of a larger pit, the Century Project, that would enable it to tap those resources.

That's one of several exploration and development projects across its mines that Goldcorp believes will enable it to increase its reserves over the next few years. Overall, the company estimates it has more than 43 million ounces of additional gold resources across its existing portfolio, which it hopes to prove.

The formula for creating wealth

While Goldcorp has a massive reserve base, what's even more important is that these are low-cost resources. Further, the company's five-year plan not only puts it on pace to increase production and reserves by 20%, but would also cut production costs by that same percentage, pushing its all-in sustaining cost from $850 an ounce to $700 an ounce. That will make it an even more profitable producer, especially if current prices hold, which could create tremendous wealth for its investors.