Mario Antonio Bertoncini
Analyst · Morgan Stanley
Thank you, Tito. Turning to Page 8, we discussed our mining performance in the second quarter. As usual, let me remind you that we convert our production by metal to our zinc-equivalent basis using full year 2017 LME prices in order to present comparable figures.
The zinc equivalent production in Nexa's mining operations totaled 135,000 tons in the second quarter of '18, in line with the first quarter of this year and 6% down when compared to second quarter of '17. A decrease of 4% in treated ore volumes and in copper grade were partially offset by the increase in zinc grade. You can observe on the top-left table on this page that our zinc contained in concentrate in the second quarter of this year was in line with the same quarter last year and 6% higher compared to the first quarter of this year. Allowing zinc equivalent production to reach 99% of the volume planned for the first half of this year.
The [indiscernible] in Cerro Lindo, we have focused on developing new galleries and stopes as planned, which will enable us to grow production in the second semester. It's important to highlight that our efforts to extend Vazante mine life, assessing the new ore body there and to keep El Porvenir operating at capacity resulted in better performance on both mines when compared to previous year. These 2 mines, Vazante and El Porvenir, accounted for 44% of zinc equivalent production in this second quarter of the year.
At the bottom-right part of the page, we have our mining cash cost after byproduct credits, which were on a consolidated basis, $0.04 per pound higher in the quarter, impacted by lower byproduct credits due to the decrease of copper, silver and gold content in concentrate and also impacted by higher operating cost in Peru due to the already known process revisions made in the second half of last year to enforce our safety conditions. These effects were partially offset by the BRL devaluation, by the real devaluation that impacted positively our Brazilian mine and lower treatment charges.
Please let's move on to Slide 9, where we present our smelting performance. As already discussed in the previous quarter, our metallic zinc production is back to full capacity this year. Our sales totaled 143,000 tons in the second quarter, a 5% increase when compared to the second quarter of the previous year of '17, driven by smelters operating at capacity as mentioned and also debottlenecking efforts, as Tito already explained. Cajamarquilla sold 82,000 tons in second quarter of '18, up 14% compared to second quarter of last year, which was impacted by heavy rainfalls and floods, as we know.
Comparing to the first quarter of this year, metal consolidated sales were 4% higher. Cash cost, net of byproducts' credit increased by 21% to $1.30 per pound in second quarter of this year. Compared to the same periods of the previous year, mainly due to higher raw material costs driven by higher zinc prices and lower treatment charges, partially offset by higher byproduct credits, Brazilian currency devaluation and the higher metallic zinc sales.
Moving on, on this Page 10, we present our revenues and EBITDA for segments. Please note that these segmented sales, on sales, not EBITDA, includes intersegment revenues that will be offset on the consolidated sales presented on the next page.
Revenues for the mining segment totaled $301 million in the second quarter of this year, an increase of 10% or $27 million when compared to the second quarter of last year, mainly due to higher metal prices.
Adjusted EBITDA totaled $116 million for the mining segment in the second quarter of this year, a 6% increase when compared to the same quarter of the previous year, mainly because of higher revenues, as I just mentioned. When comparing first half of '18 and '17, adjusted EBITDA increased by 31% to $277 million.
For the smelting division, revenues totaled $520 million in the second quarter of '18, 17% up or $77 million compared with the same period of last year, mainly due to an increase in metal production and metal prices, as presented in the previous page.
Adjusted EBITDA amounted $47 million in the second quarter of this year, a 32% increase when compared to the same quarter of last year for the smelting division.
As Tito mentioned before, Brazilian truck drivers went on strike between May 22 and 31, interrupting road transportation nationwide and partially offsetting Nexa's smelting operation as communicated to the market. The company took all necessary and appropriate measures to mitigate the impact caused by these strikes. As a result, metal production at our Juiz de Fora smelter was not affected, while production at the Três Marias smelter was partially affected due to the interrupted supply of zinc concentrate and other critical inputs. After these events, financial impact caused by such interruptions was immaterial, despite the sales backlog already explained.
Let's move on to Page 11, where we talk about the financial results. Our revenues went up 11% to $637 million in the second quarter of this year, primarily due to higher metal sales volumes and base metals prices in the global market. The higher revenues allowed us to reach an adjusted EBITDA of $163 million on a consolidated basis in this quarter, resulting in a sound margin of 26%, and an increase of 17% comparing to the same period of last year.
On the upper-right part of the slide, we present our CapEx breakdown for the period. $58 million, 6% higher than the CapEx of the second quarter of previous year and 7% higher when comparing to the 6-month period. In accordance with our strategy and plan of growing in mining, investment in this segment represented 60% of the $91 million disbursed from January into June in CapEx.
On the bottom part of this page is our sound operational free cash flow before investment/debt principal and distribution, resulting a 26% cash conversion. If we did that -- the expansion CapEx, our cash conversion goes to 34% in the first half of this year.
Let's move on to the next slide, please. As we reach the end of this first semester, we reiterate our -- all of our guidances for '18 that were released last February. Mining production in the second quarter of this year reached 135,000 tons in zinc-equivalent terms. In the first half of '18, we produced 99% of the volume planned for the period, which allows us to reinforce our annual guidance.
Production is slightly below the planned amount for the first of '18, due to delays in developing new mining gallery at Cerro Lindo. But the performance improvement in Vazante and El Porvenir partially offset this effect.
As planned, we are focusing our efforts to sustain high levels of production in Cerro Lindo during the second half of this year, which includes the development of new mining galleries at these mines, in addition to the very good levels of production in the remaining mines, particularly Vazante and El Porvenir.
The smelting metallic zinc sales totaled 143,000 tons in the quarter, while zinc oxide sales reached 9,000 tons. In the first half of this year, our smelters ran at capacity while roasters performed increased, as expected.
Weather conditions were more favorable this year than compared to last year, enabling us to operate within our planned schedule and focus our efforts on cost efficiency and enhancing our safety standards.
Let's move on, please, to the next slide, where we discuss our guidance on CapEx and project-related expenses. As said, we also reiterate our guidance for CapEx and project-related expenses for this year.
We invested $59 million during the quarter, $35 million within our mining business and $93 million within our Smelting segment and the remaining $4 million in other fronts, totaling $91 million in the semester.
CapEx was $9 million below budget in the second quarter of this year, being the most part of this difference -- around 80% of this difference explained by the depreciation of the Brazilian real, since most of the CapEx in Brazil is denominated in real and translated to dollars.
Let me remind you of our main projects -- CapEx projects for this year. First Aripuanã, the final feasibility study was 95% complete as of June 30, and the construction of the project is expected to be submitted to our Board of Directors' approval in the following months. Second, the Vazante life of mine extension, our key brownfield project, which is expected to extend the mine life of Vazante from 2022 to '27.
Third, the implementation of dry stacking tailings in Vazante. This project encompasses the installation of a press filtering tailings plant for the dry disposal of these materials in piles, replacing wet tailings disposal directly into the dam. During the second quarter of this year, we attained 28% of the project overall progress. The detailed engineering progressed to 90% in this period.
The fourth main project is our process conversion at the Cajamarquilla smelter from Goethite to Jarosite, as already explained in previous quarters. This is expected to improve the zinc recovery at that smelter by 3%.
The expenses on mineral exploration and project development advance, and we expect to meet the guidance as planned. In this regard, I would like to make an observation. On the project development line, we adjusted the amount to $30 million to be expensed this year. This is not a guidance change, we are not changing the guidance. That's because the remaining part, the other $24 million that used to be on this line was reclassified. Out of this $24 million, we classified $14 million where we classified -- reclassified to CapEx and the other $10 million to corporate project expenses, okay?
Let's move onto Slide 14 where, where we present our capital structure. Following our financial discipline and cash and leverage targets, we amortized in the first half of this year approximately $60 million in export credit notes in order to reduce our financial interest costs. We also renegotiated some outstanding debts with banks, amounting $200 million during the quarter -- during this last quarter. Extending the maturity from November 2021 to May '23 and reducing cost from 250 bps to 130 bps per annum over LIBOR on this $200 million. As a result, the average maturity of the total debt was 6.4 years at an average cost of 4.8% per annum in dollar terms as of June 30.
On the pie chart, we present the debt breakdown. In terms of currency, 92% of total debt is denominated in U.S. dollars, and our 2 bonds outstanding account for 73% of this total debt. By the end of second quarter, Nexa reported a cash balance of $1.1 billion, and a net debt of $264 million, resulting in a 0.35x net debt-to-EBITDA ratio when considering the last 12 months adjusted EBITDA for this purpose.
As you can see on the rating table, our credit was reinforced by the 3 major rating agencies even after the Brazilian [ saw ] down-rating in the recent past, [ which ] not only confirmed the BBB- rating, but also revised our outlook to stable.
Now, I pass back to Tito, so he can talk about our projects and priorities for this year.