Someone on a forum gave you a formula — run these four checks first

Someone on r/DIYfragrance stated the brief clearly:

"I'm trying to build a very clean, light, modern suede/leather accord… I'm not looking for a dark, smoky, animalic, vintage or heavy leather. I'm trying to achieve something much more like Tom Ford White Suede — very blonde, soft, clean, smooth and almost textile-like."

"I already have Suederal LT, which is giving me a nice suede effect, but I'm finding that on its own it can lean a little too much toward dark suede / leather handbag / boot for what I'm trying to achieve."

"I've also tried Safraleine, but I'm finding that the saffron/medicinal aspect can become a little too prominent."

One reply supplied a complete formula, 13 materials summing to 1000:

Material	Parts
Hedione	220
Iso E Super	200
Suederal LT	150
Methyl Ionone Gamma Coeur	120
Helvetolide	80
Ambrettolide	60
Cashmeran	45
Cedramber	40
Linalyl Acetate	35
Pink Pepper CO2	15
Safraleine (10% in DPG)	20
Pyralone / IBQ (1% in DPG)	10
Damascenone Total (1% in DPG)	5

And about a different formula linked in the same thread, someone wrote:

"Just don't have your hopes too high, it's probably an AI formula." (MisterTomato)

I have no way of telling whether any formula was AI-generated. But four things can be checked, and afterwards you will know more about the formula than its author told you.

The short version

• One — the dilution arithmetic. Three materials are listed as dilutions. The IBQ, "10 parts of a 1%", is 0.01% of neat material — 97× less than the 1% it appears to be in the table. Safraleine is off by 9.7×.
• Two — do the doses match practice? Hedione is 22.75% against a corpus median of 7.89% (2.9×); Iso E Super 20.68% against 6.46% (3.2×); methyl ionone 12.41% against 5.50% (2.3×). It deliberately overdoses the transparent materials.
• Three — can the materials be looked up? Hedione (269 formulas), Iso E Super (110), linalyl acetate (207) and methyl ionone (135) are corpus staples. But Suederal appears 0 times in 954 formulas, Pink Pepper CO2 also 0, Cedramber 1, Safraleine 8.
• Four — can the forum consensus be tested? Three people independently say ionones soften leather. The corpus has only 9 formulas with leather or suede in the title; 3 of them contain ionones (33%), against a corpus baseline of 37%. Nine formulas cannot answer this, and I am not going to pretend otherwise.
• And when the poster says "cashmeran smells like wet mud to me", the author replies "cashmeran smells differently to me". That has evidence behind it: a 2012 twin study measured heritability of 0.41 to 0.71 for several chemosensory traits, and its stimulus panel included a perfumery musk.

One: the dilution arithmetic

The formula is written responsibly — three materials carry an explicit dilution strength. But those labels need converting before you know the actual quantity.

Material	Listed parts	Looks like	Actual neat	Off by
Safraleine (10% DPG)	20	2.0%	0.21%	9.7×
Pyralone / IBQ (1% DPG)	10	1.0%	0.01%	97×
Damascenone Total (1% DPG)	5	0.5%	0.005%	97×

IBQ is twelfth in the table and looks like 1%. It is 0.01% — one part in ten thousand.

That is not the formula's error; the author labelled it clearly. The error happens in the reader. Buy from this table and weigh 10 parts of neat IBQ straight in, and you make something entirely unlike the author's. IBQ carries strength rank 3, the highest, with evaluation recommended at 10% or less. A hundredfold overdose ends the formula.

Incidentally, of the 1000 parts, 32.85 (3.3%) is DPG carried in by the dilutions. Not much here, but in a formula with more dilutions the DPG starts occupying real volume.

How to run this check: multiply every material with a stated strength back out, and recompute the total. It takes under five minutes.

Two: do the doses match practice?

Comparing the 13 materials' actual shares against median doses across 954 published formulas:

Material	This formula	Corpus median	Ratio
Hedione	22.75%	7.89%	2.9×
Iso E Super	20.68%	6.46%	3.2×
Methyl ionone gamma	12.41%	5.50%	2.3×
Linalyl acetate	3.62%	6.00%	0.6×
Ambrettolide	6.20%	1.29%	4.8×
Helvetolide	8.27%	2.78%	3.0×
Cashmeran	4.65%	0.83%	5.6×
Safraleine	0.21%	0.26%	0.8×

This is not a formula at ordinary doses, and that is deliberate.

Hedione and Iso E Super take 43% between them, both at three times the corpus median. What those two share is diffusion, transparency, and not occupying space — they open the room out rather than filling it.

The lightness the poster wants is not built here by using less leather (Suederal is 15.5%, which is not small). It is built by overdosing the transparent materials. That is a measurable technical decision, and it answers his original problem: if Suederal reads too dark alone, the fix is not less Suederal but forty per cent of transparent material stacked around it.

Safraleine at 0.21% sits almost exactly on the corpus median of 0.26%. The poster said Safraleine's medicinal side takes over — if he has been using it far above 0.21%, that is where the problem lives.

Three: do these materials exist in published formulas?

This check produces the most telling result.

Material	Appearances in 954	Median dose
Hedione	269 (28.2%)	7.89%
Linalyl acetate	207 (21.7%)	6.00%
Methyl ionone	135 (14.2%)	5.50%
Iso E Super	110 (11.5%)	6.46%
Damascenone	49 (5.1%)	0.44%
Ambrettolide	44 (4.6%)	1.29%
Cashmeran	32 (3.4%)	0.83%
Quinolines (all IBQ spellings)	28 (2.9%)	1.12%
Helvetolide	15 (1.6%)	2.78%
Safraleine	8 (0.8%)	0.26%
Cedramber	1 (0.1%)	—
Suederal	0	—
Pink Pepper CO2	0	—

The formula splits in two.

The half carrying the weight — Hedione, Iso E Super, linalyl acetate, methyl ionone, 59% together — are all corpus staples you can watch being used across hundreds of formulas.

And the half giving it its identity — Suederal, Pink Pepper CO2, Cedramber, Safraleine — barely exists in published formulas.

That explains why the poster cannot find a White Suede formula. The effect he wants is built on proprietary bases and modern materials, and those do not appear in published work: Suederal is a compounded base, not a single molecule, and published formulas generally do not include bases because nobody else could reproduce them.

This is a structural limit, not a failure to search hard enough.

The corpus's leather formulas are the kind he doesn't want

Pulling formulas with leather, suede or cuir in the title gives 9. Their most frequent materials:

Material	In the 9	Corpus baseline
Sandalwood oil	3 (33%)	6.3%
Clary sage oil	2 (22%)	2.3%
Coumarin	2 (22%)	23.6%
Olibanum resinoid	2 (22%)	0.9%
Geranium oil bourbon	2 (22%)	5.0%
Galbanum oil	2 (22%)	5.6%

Sandalwood, clary sage, olibanum, galbanum — a classical chypre roster, which is exactly the "dark, vintage, heavy leather" the poster ruled out.

(A few of those 9 contain m-xylene, octane, dodecane and ethyl laurate at 31.5%. That does not look like perfumery; it looks like GC-MS reconstruction data or an industrial formulation that got into the set. I left them in the count and draw nothing from them.)

The corpus has nothing like White Suede. It is a post-2000s effect, and the corpus's centre of gravity is clearly earlier.

Four: that consensus, the corpus cannot answer

Three people in the thread point the same way:

"You could start with Safraliene, IBQ and some ionones. Violet molecules definitely soften harsh leather but quite difficult to balance." (logocracycopy)

"I would start off with methyl ionone Gamma." (jnill1995)

"I have suederal and going to mix with methyl Ionone Gamma Couer." (the poster)

And methyl ionone is the fourth-largest item in the posted formula at 12%.

This sounds like a testable consensus, and I cannot test it.

The corpus holds 9 leather formulas, of which 3 contain ionones or irones — 33%. The corpus baseline is 37%.

33% against 37%, on a sample of 9. That gap is entirely inside the noise, and it even points the wrong way. I cannot say the corpus fails to support ionones softening leather, because 9 is not enough to refute it either. All I can say is that this consensus is not checkable with the data I have.

I am writing this section out deliberately, because this series has run many genre-enrichment analyses — lavender's fougère at 7.3×, hexyl salicylate's fruity at 2.3× — and those rested on 39 to 57 formulas. Nine is not enough, and reporting a 33%-versus-37% ratio on an inadequate sample invites the reader to treat it as a result. It is not one.

"It's probably an AI formula" — what I can check

MisterTomato's warning is a live problem now. I cannot establish provenance, but all four checks above are runnable, and they catch exactly where unreliable formulas give themselves away:

Check	How	What it catches
The total	Add the parts	A total that doesn't land is usually a transcription gap or an invention
Dilution labels	Is a strength stated? If so, multiply it back	A strong material with no strength stated is a red flag
Dose range	Compare against published medians	A tenfold gap needs a reason
Material existence	Look up supplier count and CAS	No such material, or zero suppliers, deserves caution

The formula above passes all four. The total is exactly 1000, all three dilutions carry a strength, the deviations in dose have a consistent direction (overdosed transparent materials), and every material is obtainable. Whoever wrote it, the arithmetic holds.

And the author's own instructions matter more than the formula:

"My recommendation is to dilute ingredients to 10% as a starting point and either by using the scent strip process or very small 1 or 2 grams batches adjusting as needed until you achieve what you are looking for. Microbatches are your friend."

"Cashmeran smells like wet mud to me"

One exchange in the thread deserves the most serious treatment in this piece.

Poster: "to me cashmeran smells like wet mud, but can't see how this mix would soften into the luxury soft sweater comforting smell?"

Author: "Cashmeran smells differently to me. Thats why this hobby is so difficult. There is no way I would be able to provide a ready to go formula that will smell pleasant to you as your nose differs from mine."

"As some examples, Halfeti smells absolutely beautiful and lovely to me, to others in my family not so much. Padamber, Cedrol are horrific to me but pleasant to my wife…"

That is not politeness. It has been measured.

In 2012, Knaapila and colleagues published a twin study in Chemical Senses. Adult twins rated the chemosensory aspects of water, sucrose, sodium chloride, citric acid, ethanol, quinine hydrochloride, PTC, potassium chloride, calcium chloride, cinnamon, androstenone, Galaxolide™, cilantro and basil.

There is a perfumery musk on that list.

The findings: for most traits, individual differences were stable over time, and some traits were heritable, with h² from 0.41 to 0.71. Subjects were genotyped for 44 single nucleotide polymorphisms within and near taste and smell genes. The association analyses confirmed previous genotype-phenotype results for PTC, quinine and androstenone, and detected new associations: basil with the bitter taste receptor gene TAS2R60, cilantro with variants in TRPA1, GNAT3 and TAS2R50, and the flavour of ethanol with variation in an olfactory receptor gene (OR7D4) and a gene encoding an epithelial sodium channel subunit (SCNN1D).

The paper's conclusion is direct: person-to-person differences in the taste and smell perception of simple foods and drinks are partially accounted for by genetic variation within chemosensory pathways.

For scale, a 2022 dataset from central Russia measured androstenone discrimination, intensity and pleasantness in 807 residents aged 9 to 84. The authors note in passing that androstenone is "perceived as an unpleasant odor by about a quarter of the population".

A quarter. That is not a fringe.

So the author's "your nose differs from mine" is literally correct, and it has a specific consequence for building someone else's formula. A formula reproduces molecules, not perception. What you weigh out at 1000 parts is the same liquid the author has, with no guarantee that it is the same perfume.

The limits of both papers should be stated. Knaapila's group measured specific stimuli including androstenone and Galaxolide; they did not measure Cashmeran. The Russian dataset measured androstenone, not any perfumery material. What I cite them for is that individual variation is real, partly heritable, and not small — not that Cashmeran has a known polymorphism, for which I have no evidence.

How I handled this round

I expected check four — ionones softening leather — to be the strongest section. Three independent people saying the same thing, and 954 formulas to test it against, is the shape this series handles best.

Running it gave 9 leather formulas. 33% against 37%.

I briefly considered widening the keywords to grow the sample, folding in chypre, tobacco and animalic, which would have reached twenty or thirty. I stopped, because that would mean changing the definition to make the sample adequate, not because chypre is the same thing as leather. This series has applied genre labels from title keywords since the first round, and changing the rule mid-way for one question would destroy the comparability of every number.

So the section went from "testing a consensus" to "I cannot answer this". One of four checks comes back blank, and I left it in, because a blank is also a result.

For anyone handed a formula

• Multiply the dilutions back out first. The IBQ marked "1%" here is actually 0.01%, off by 97×.
• Compare against published doses. A threefold gap is usually a deliberate technical decision (as with the transparent materials here); a hundredfold gap is usually a misreading.
• Check that the materials exist. A good formula you cannot buy the materials for is not a formula you can build.
• Bases never appear in published formulas. If the effect you want rests on a compounded base like Suederal, you will not find it in published work, ever.
• Work in microbatches. One or two grams, with materials pre-diluted to 10%.
• A formula reproduces molecules, not noses. What you smell and what the author smells are not guaranteed to match, and the scale of that is a quarter of the population.

What this doesn't establish

• I have not made this formula and have not smelled it. What is checked here is its arithmetic, doses and availability, not whether it smells good.
• Nine leather formulas cannot test any genre-level claim. The ionone section is a blank, not a refutation.
• Corpus median doses are weight shares within a formula, different from concentration in a finished product, and the corpus itself skews towards what gets published.
• "Suederal appears 0 times" measures these 954 published formulas, not the market. Suederal is a real, widely used commercial base; it just does not appear in published formulas.
• Knaapila 2012 did not measure Cashmeran. What I cite is the general finding that individual differences are partly explained by genetic variation, not any result about Cashmeran.
• Klyuchnikova 2022 is a data paper measuring androstenone. The "quarter of the population" figure is prior knowledge the authors restate in the abstract; I use it for scale, not as that paper's new finding.
• I have no way to determine whether any formula is AI-generated. The four checks catch arithmetic and availability problems, which are independent of provenance. A bad human formula and a bad AI formula give themselves away in the same places.