MTRN vs KALU vs MP vs CSTM

For growth investors, MP Materials Corp.

(MP) is the stronger pick with 35. 1% revenue growth year-over-year, versus 6. 0% for Materion Corporation (MTRN). Constellium SE (CSTM) offers the better valuation at 17. 1x trailing P/E (10. 4x forward), making it the more compelling value choice. Analysts rate Materion Corporation (MTRN) a "Buy" — based on 10 analyst ratings — the highest consensus in this comparison. The "better buy" depends entirely on your goals: growth investors should weight revenue trajectory, value investors should weight P/E and PEG, and income investors should weight dividend yield and streak.

On trailing P/E, Constellium SE (CSTM) is the cheapest at 17.

1x versus Materion Corporation at 53. 4x. On forward P/E, Constellium SE is actually cheaper at 10. 4x. The PEG ratio (P/E divided by earnings growth rate) is the most growth-adjusted single valuation metric: Kaiser Aluminum Corporation wins at 0. 62x versus Materion Corporation's 0. 82x — a PEG below 1. 0 traditionally signals the market is underpricing earnings growth.

Over the past 5 years, Materion Corporation (MTRN) delivered a total return of +155.

6%, compared to +40. 7% for Kaiser Aluminum Corporation (KALU). Over 10 years, the gap is even starker: MTRN returned +724. 3% versus KALU's +135. 1%. Past returns do not guarantee future results, and the stock with the higher historical return may already have its best growth priced in.

By beta (market sensitivity over 5 years), MP Materials Corp.

(MP) is the lower-risk stock at 1. 40β versus Constellium SE's 1. 85β — meaning CSTM is approximately 32% more volatile than MP relative to the S&P 500. On balance sheet safety, MP Materials Corp. (MP) carries a lower debt/equity ratio of 44% versus 2% for Constellium SE — giving it more financial flexibility in a downturn.

By revenue growth (latest reported year), MP Materials Corp.

(MP) is pulling ahead at 35. 1% versus 6. 0% for Materion Corporation (MTRN). On earnings-per-share growth, the picture is similar: Materion Corporation grew EPS 1179% year-over-year, compared to 12. 3% for MP Materials Corp.. Over a 3-year CAGR, MTRN leads at 0. 6% annualised revenue growth. Higher growth typically commands a higher valuation multiple — check whether the premium P/E or P/S is justified by the growth rate using the PEG ratio.

Materion Corporation (MTRN) is the more profitable company, earning 4.

2% net margin versus -31. 2% for MP Materials Corp. — meaning it keeps 4. 2% of every revenue dollar as bottom-line profit. Operating margin tells a similar story: MTRN leads at 6. 5% versus -44. 6% for MP. At the gross margin level — before operating expenses — MTRN leads at 16. 7%, reflecting greater pricing power or product mix advantage. Stronger margins indicate durable pricing power, lower cost of revenue, or higher mix of software/services. They are one of the clearest signs of business quality.

The PEG ratio (forward P/E divided by expected earnings growth rate) is the most precise measure of undervaluation relative to growth potential.

By this metric, Kaiser Aluminum Corporation (KALU) is the more undervalued stock at a PEG of 0. 62x versus Materion Corporation's 0. 82x. A PEG below 1. 0 is traditionally considered the threshold for growth-adjusted undervaluation. On forward earnings alone, Constellium SE (CSTM) trades at 10. 4x forward P/E versus 274. 3x for MP Materials Corp. — 263. 9x cheaper on a one-year earnings basis. Analyst consensus price targets imply the most upside for MP: 13. 2% to $78. 25.

In this comparison, KALU (1.

8% yield), MTRN (0. 3% yield) pay a dividend. MP, CSTM do not pay a meaningful dividend and should not be held primarily for income.

For long-horizon retirement investors, MP Materials Corp.

(MP) is the stronger choice — it scores higher on the combination of lower volatility, dividend reliability, and long-term compounding (+591. 3% 10Y return). Constellium SE (CSTM) carries a higher beta of 1. 85 — meaning larger drawdowns in market downturns, which matters significantly when you cannot wait years for a recovery. Both have compounded well over 10 years (MP: +591. 3%, CSTM: +503. 1%), confirming both are viable long-term holds — but the lower-volatility option typically results in less emotional selling during corrections. Retirement portfolios generally favour predictability over maximum returns. Consult a financial advisor before making allocation decisions.

Both stocks operate in the Basic Materials sector, making this a peer-level intra-sector comparison — the same macro tailwinds and headwinds will affect both.

In terms of investment character: MTRN is a small-cap quality compounder stock; KALU is a small-cap quality compounder stock; MP is a mid-cap high-growth stock; CSTM is a small-cap high-growth stock. KALU pays a dividend while MTRN, MP, CSTM do not, making them suitable for different income and tax situations. These fundamental differences mean investors should not choose between them on a single metric — the "better stock" depends entirely on which of these characteristics aligns with your investment strategy.