Key Highlights:

  • Mineral Resources was promoted to the S&P/ASX 50 from 21 September, but fell about 12.6% in the week to 18 September as lithium stocks sold off.
  • Vulcan Energy traded at $2.07 on 24 September, close to a 52-week low of $2.05 and well below its high of $7.52, even though it has secured a €2.2 billion funding package.
  • Next up: spodumene prices, the RBA decision on 29 September, October quarterly reports and construction progress at Vulcan's Lionheart project.
  • Upcoming company updates and execution against stated plans remain central to the next phase for both stocks.

For Mineral Resources, the next chapter depends on whether the lithium price recovery holds up after its promotion to the S&P/ASX 50. For Vulcan Energy, it depends on building its funded German lithium project and winning back investors who have pushed the shares to a 52-week low.

Lithium's recovery meets a sharp pullback

Lithium stocks had a strong run in 2026 as prices recovered from the 2024–25 slump. Benchmark spodumene concentrate (SC6) rose about 57% in the first half of 2026, from around US$1,560–1,590 a tonne in January to US$2,428 a tonne in early June, . It was still above US$2,200 a tonne in early September, at US$2,254 FOB Australia on 2 September.

That analysis also flagged the main risk to the rally. Around 220,000 tonnes of lithium carbonate equivalent in new African Supply is expected in 2026. It warned that the window between "recovery confirmed" and "oversupply re-emerges" may be narrower than bulls assume. In mid-September, lithium stocks were sold after their earlier gains. on 17 September whether an "evolving development" could hit producers including Liontown, Mineral Resources and PLS.

Rates add to the pressure. The RBA cash rate is 4.35% after a rise in May. Commonwealth Bank economists expect another 25 basis point increase at the 28–29 September meeting, and markets are pricing roughly a 90% chance of a move. Higher rates tend to hurt capital-heavy developers most, but they also affect indebted producers.

Mineral Resources (ASX:MIN): new index status, same volatility

Mineral Resources is a Perth-based Mining services, iron ore and lithium group. Its lithium interests include the Wodgina and Mt Marion operations in Western Australia. Its iron ore Business includes the Onslow Iron project in the Pilbara. That mix gives it exposure to both lithium and iron ore prices.

Its standing in the market improved in the September quarterly rebalance. S&P Dow Jones Indices announced on 4 September that Mineral Resources and NEXTDC would join the S&P/ASX 50 from 21 September, replacing Cochlear and WiseTech Global. Promotion to a higher index can bring buying from funds that track it, but much of that is usually priced in before the effective date.

Since the announcement, the shares have gone backwards. a fall of about 12.6% in the week to 18 September, leaving the stock at $53.54. it at $52.41, down 3.27% in that session. That puts its Market Value at around $10.8 billion, within a 52-week range of $38.06 to $73.95. The pullback suggests that some investors took profits on lithium stocks after a strong year, rather than reacting to a new company-specific problem.

Vulcan Energy (ASX:VUL): funded, but out of favour

Vulcan Energy is building a geothermal lithium and renewable energy business in Germany's Upper Rhine Valley. It plans to extract lithium from geothermal brine and produce battery-grade lithium chemicals for European customers. The company's Phase One Lionheart project is its flagship development. Vulcan has announced a financing package of €2.2 billion, or about A$3.93 billion, which it says fully funds Phase One. Carmaker Stellantis is among its backers.

The share price has moved the other way. Vulcan at $2.07 on 24 September, down 5.05% that day. That was just above a 52-week low of $2.05 and far below a 52-week high of $7.52. Its market value was about $991 million, well below the size of the Lionheart funding package. According to that data, three analysts rate the stock a strong buy, with an average published price target of $7.25. That is a very large gap to the current price, and it shows how much analysts and the market disagree.

Vulcan joined the S&P/ASX 200 in an earlier March rebalance. With its market value now near $1 billion, investors may watch whether it stays in the index at future reviews. It was not on the list of S&P/ASX 200 removals in September. Those were EVT, GrainCorp, GQG Partners, Pantoro Gold and Tuas.

Two very different ways to play lithium

The two companies share a sector but are at different stages. Mineral Resources already produces lithium and iron ore, so its Earnings respond fairly directly to Commodity prices. Its share price has swung with the lithium cycle. Vulcan does not yet make lithium at scale. Its value depends on executing a large, complex project on time and on budget, and on lithium prices when production begins.

That affects how each responds to news. A move in spodumene prices can shift Mineral Resources' earnings outlook quickly. For Vulcan, construction milestones, cost updates and Loan drawdowns are likely to matter more than month-to-month price changes. Both remain exposed to risk sentiment: in sell-offs, investors often cut high-beta resource developers first.

What investors could watch next

For both companies, lithium prices are the main external factor. If new African supply arrives and pushes SC6 back towards long-run consensus assumptions of about US$1,500 a tonne, the 2026 rally could face pressure. If prices stay above US$2,000 a tonne, earnings upgrades may continue.

The RBA's decision on 29 September and its guidance on further increases will affect sentiment towards resource companies that need a lot of capital. Quarterly activity reports, which ASX miners usually release in late October, should show Mineral Resources' production and costs at its lithium and iron ore operations. For Vulcan, investors may watch for construction updates at Lionheart, drawdowns under the financing package and any change to its production timetable. Annual general meetings, usually held in October and November, may also bring management commentary.

The bottom line

Mineral Resources has joined the S&P/ASX 50 at a time when lithium stocks are under pressure. Its outlook depends heavily on whether spodumene prices hold their gains. Vulcan Energy has the funding in place for its first phase, but the market is heavily discounting the project, and the shares are near their lows. For both companies, the coming months will be shaped by lithium supply, interest rates and whether their operations or construction progress as planned.