Phosphor Bronze · Guitar Strings
Pyramid Cleopatra Coated Phosphor Bronze CLEO-XII Acoustic Strings Medium 12-54
Lower PFAS concern; traditional metal acoustic strings are unlikely to contain fluorinated compounds.
Phosphor bronze acoustic strings are metal-based with no inherent reason to contain PFAS coatings. Acoustic guitar strings historically use bronze alloys without water-repellency or non-stick treatments that would require fluorochemicals.
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Phosphor bronze strings (copper-tin-phosphorus alloy)
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
Why this grade
Category baseline
other is a category where PFAS exposure is more common.
No PFAS disclosure
No public statement about PFAS in this product.
Safe base material
Made from a material with no inherent PFAS use (ceramic, mineral, or natural fiber).
The full breakdown
What it's made of and why it matters
Phosphor bronze strings are a copper-tin-phosphorus alloy designed for acoustic guitars, offering brightness and durability without synthetic coatings that introduce polymer hazards. The phosphorus acts as a deoxidizer during manufacturing, stabilizing the alloy rather than remaining as a residual contaminant. Unlike nylon or polymer-coated strings, bare phosphor bronze eliminates concerns about microplastics, BPA, or phthalate leaching during use. The 12-54 gauge range (medium tension) is standard for acoustic guitars and carries no material-specific toxicity issues at these dimensions.
The brand's record and disclosure
Pyramid (Pyramid Strings GmbH, Germany) maintains minimal public disclosure on chemical composition or manufacturing practices, with no published certifications for heavy metal content, allergen labeling, or environmental testing. No major recalls or contamination incidents are documented in public safety databases for their acoustic string lines. The brand's silence on PFAS and other chemical safety metrics is typical of the guitar string industry, which lacks mandatory disclosure frameworks like those in cookware or food storage.
How it compares in its category
Phosphor bronze is the standard acoustic string material across all price tiers and brands; Pyramid's formulation is chemically indistinguishable from competitors like D'Addario, Elixir (uncoated), or Ernie Ball in the bare-metal category. Coated alternatives (Elixir, John Pearse Nanoweb) introduce polymer layers that extend string life but introduce minimal but nonzero microplastic and coating-degradation risks. Pyramid's uncoated approach represents the simplest, lowest-chemical-burden option in the category.
If you buy it
Store strings in a dry, cool environment to slow oxidation and corrosion; humidity accelerates tarnishing but does not create safety hazards. Replace strings every 3-6 months depending on playing frequency, or when they sound dull or show visible rust spots, as oxidized metal does not pose ingestion or leaching risks but degrades tone. Clean hands before playing to reduce acid and sweat transfer, which accelerates corrosion. No special disposal precautions are needed; strings can enter standard metal recycling or trash.
Beyond PFAS: other things we checked
Established hazard classes for this product type, assessed from public information. These never change the PFAS grade; a Likely flag caps the Verdict at “Buy with care.”
Copper-tin alloy metal reactivity
Phosphor bronze does not leach copper or tin into skin, sweat, or saliva at levels that pose health concern during normal playing. No occupational or consumer poisoning incidents are documented from acoustic string contact.
Corrosion and oxidation byproducts
As strings age, surface oxidation creates copper oxide and tin oxide patina, which can stain fingers with minor discoloration but poses no systemic toxicity if accidentally ingested in trace amounts during playing.
Manufacturing residues or heavy metal contamination
No public testing, recalls, or regulatory findings document lead, cadmium, or other heavy metals in Pyramid phosphor bronze strings. Standard alloy purity is assumed but unverified by independent third-party lab data.
Nickel or allergen content
Phosphor bronze alloys do not intentionally contain nickel; contact dermatitis from string playing is rare and typically linked to sweat accumulation rather than the metal itself. No allergen labeling is provided by the manufacturer.
What we don’t know
This grade is a model-based estimate from public materials, coatings, and brand disclosure at 82% confidence. It is not a lab result.
No independent PFAS lab test is on record for this exact product. A lab test could move the score in either direction.
The brand has not made a specific, verifiable PFAS-free statement, so part of this score reflects that missing disclosure rather than a confirmed material.
Formulations and coatings change between production runs. Always check the current label before buying.
Safer alternatives in Guitar Strings
Martin
Retro Acoustic Guitar Strings
Phosphor bronze, stainless steel, nylon wound
Lower concern, acoustic guitar strings typically use established metals and nylon without water-repellent coating or nonstick coatings.
✓Bare metal or glass, no coating at all
Acoustic360
Ernie Ball Everlast Acoustic Guitar Strings
Phosphor bronze/stainless steel wound on steel core
Lower PFAS concern, acoustic guitar strings use standard metal materials with no known fluorochemical treatments.
✓Bare metal or glass, no coating at all
Dean Markley
Electric Guitar Strings
Steel alloy strings (nickel-plated or stainless steel core)
Lower PFAS concern, steel strings lack typical PFAS applications, but no brand disclosure exists.
✓Bare metal or glass, no coating at all
More guitar strings grades
How we score: every product runs through the same public 0–100 rubric based on materials, coatings, brand disclosure, lab findings, and recalls. See the full methodology → Spotted a mistake? Report an error.