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Gem DiamondsSTU:ZVW +12.39%43 Pretax Margin % is 5.25% as of Jun. 2026, which is 62% below its 10-year median of 13.68. GuruFocus rates STU:ZVW with a GF Score™ of 43/100 and a GF Value™ of €0.06 (Significantly Overvalued). The stock has 9 warning signs investors should review. Among 851 Metals & Mining companies, Gem Diamonds ranks worse than 76.73% on this metric.
Pre-Tax margin is calculated as Pre-Tax Income divided by its Revenue. Gem Diamonds's Pre-Tax Income for the
six
months ended in Jun. 2026 was €2.72 Mil. Gem Diamonds's Revenue for the
six
months ended in Jun. 2026 was €51.85 Mil. Therefore, Gem Diamonds's pretax margin for the quarter that ended in Jun. 2026 was 5.25%.
The historical rank and industry rank for Gem Diamonds's Pretax Margin % or its related term are showing as below:
STU:ZVW'
s Pretax Margin % Range Over the Past 10 Years
Min: -93.54 Med: 13.68 Max: 29.45
Current: -60.94
STU:ZVW's Pretax Margin % is ranked worse than 76.73% of 851
companies
in the Metals & Mining industry
Industry Median: 6.16
vs STU:ZVW: -60.94
The pretax margin, as know as pretax profit margin, is widely used to measure the operating efficiency of a company before deducting taxes.
The pretax margin is sometimes preferred over the net margin as tax expenditures can make profitability comparisons between companies misleading.
It is a useful tool to compare companies operating in the same sector and less effective when comparing companies from other sectors as each industry generally has different operating expenses and sales patterns.
The long term trend of the pretax margin is a good indicator of the competitiveness and health of the business.
Gem Diamonds Pretax Margin % Related Terms
Gem Diamonds Pretax Margin % Historical Data
* Premium members only.
The historical data trend for Gem Diamonds's Pretax Margin % can be seen below:
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
For the Other Precious Metals & Mining subindustry, Gem Diamonds's Pretax Margin %, along with its competitors' market caps and Pretax Margin % data, can be viewed below:
* Competitive companies are chosen from companies within the same industry, with headquarter located in same country, with closest market capitalization; x-axis shows the market cap, and y-axis shows the term value; the bigger the dot, the larger the market cap. Note that "N/A" values will not show up in the chart.
Gem Diamonds Pretax Margin % vs Metals & Mining Industry
For the Metals & Mining industry and Basic Materials sector, Gem Diamonds's Pretax Margin % distribution charts can be found below:
* The bar in red indicates where Gem Diamonds's Pretax Margin % falls into.
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
Gem Diamonds (STU:ZVW) has a Pretax Margin % of 5.25% as of Jun. 2026. Pre-Tax margin is the ratio of total pre-tax income to net sales. View historical data on Gem Diamonds and its competitors. This is 62% below median its historical median of 13.68. According to the industry distribution chart, Gem Diamonds ranks #653 out of 851 companies in the Metals & Mining industry, placing it in the top 76.7%.
Is Gem Diamonds' Pretax Margin % too high?
Gem Diamonds' current Pretax Margin % of 5.25% is 62% below median its 10-year median of 13.68. The Metals & Mining industry median Pretax Margin % is 6.16. Gem Diamonds' value of 5.25% is 14.8% below this industry median. Based on the distribution chart, Gem Diamonds ranks #653 out of 851 companies in the Metals & Mining industry, which is in the bottom quartile relative to peers. Overall, Gem Diamonds has a GF Score™ of 43/100 and is considered Significantly Overvalued, reflecting its overall financial health beyond just this single metric.
How does Gem Diamonds' Pretax Margin % compare to HL?
According to the Metals & Mining industry distribution chart, Gem Diamonds ranks #653 out of 851 companies for Pretax Margin %. This places Gem Diamonds in the lower half of its industry. The industry median Pretax Margin % is 6.16. Gem Diamonds' value of 5.25% is 14.8% below this benchmark. While the company's 10-year median is 13.68 vs. the industry median of 6.16, Gem Diamonds has consistently been below the industry average. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Pretax Margin % for a Metals & Mining company?
The median Pretax Margin % among Metals & Mining companies is 6.16, based on 851 companies in the industry. Companies in the top quartile (top 25%) have a Pretax Margin % significantly above this median, while those in the bottom quartile fall well below. However, Pretax Margin % should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Gem Diamonds's current Pretax Margin % of 5.25% is 14.8% below the industry median. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high Pretax Margin % mean?
A high Pretax Margin % can signal that a stock is expensive relative to its fundamentals. Pre-Tax margin is the ratio of total pre-tax income to net sales. View historical data on Gem Diamonds and its competitors. For the Metals & Mining industry, the median Pretax Margin % is 6.16 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Gem Diamonds's current Pretax Margin % is 5.25%, which is 62% below median its own 10-year median of 13.68. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Gem Diamonds stock overvalued right now?
Based on GuruFocus' analysis, Gem Diamonds (STU:ZVW) is currently considered Significantly Overvalued. The stock's GF Value™ is €0.06, compared to a current price of €0.13 — trading 111.7% above its estimated fair value. The current Pretax Margin % is 5.25%, which is 62% below median its 10-year median of 13.68 and 14.8% below the Metals & Mining industry median of 6.16. Gem Diamonds' overall GF Score™ is 43/100 with 9 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Pretax Margin % calculated?
Pretax Margin % is calculated from a company's financial statements. For Gem Diamonds (STU:ZVW), the current Pretax Margin % is 5.25% as of Jun. 2026. GuruFocus calculates this using data sourced from SEC filings and annual reports. See the calculation section and 30-year financial data on this page for the full breakdown.
Is Gem Diamonds (STU:ZVW) Overvalued in 2026?
Based on GuruFocus' analysis, Gem Diamonds stock appears to be overvalued.
The current stock price of €0.13 is trading 111.7% above its estimated GF Value™ of €0.06.
GuruFocus considers Gem Diamonds to be Significantly Overvalued.
Key valuation signals for STU:ZVW:
Pretax Margin %: 5.25% (62% below median its 10-year median of 13.68)
GF Value™: €0.06 vs. price of €0.13 (111.7% above fair value)
Industry Position: 14.8% below the Metals & Mining median (#653 of 851)
No single metric tells the full story. See the STU:ZVW stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Gem Diamonds Ltd is a United Kingdom-based company engaged in the exploration and development of diamond mines. The company's geographical segments include Lesotho (diamond mining activities); Belgium (sales, marketing, and manufacturing of diamonds); and BVI, RSA, the UK, and Cyprus (technical and administrative services) and Botswana (diamond mining activities, currently on care and maintenance). It generates maximum revenue from the Belgium region. Its projects include Letseng Diamond mine and Ghaghoo Diamond mine. The company's revenue is derived from mining activities, polished manufacturing margins, and diamond analysis and manufacturing services.
43GF Score
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