Does It Take Millions Of Years To Form Opal?
Bodie Hodge, M.Sc., B.Sc., PEI
Biblical Authority Ministries, March 31, 2026 (Donate)
Opals are beautiful gemstones! In fact, many people wear
them in pricey jewelry. I was taught it takes millions of years to form opals.
Many, today repeat this claim. Consider this quote:
“How long does it take an opal
to form? 30 million years ago, when lots of silica was released into a solution
that filled cracks in the rocks, layers in clay, and even some fossils, the
very beginnings of the creation of opal started. It’s believed that it takes
about 5 to 6 million years for a 1cm opal to mature.”[1]
Does it really take millions of years to make opals? Keep in
mind that no one has observed opals taking millions of years to form—nor has it
been repeated over millions of years. Thus, it isn’t science, but a worldview belief—that
of the religion so secular humanism (e.g., naturalism and long ages come out of
this religion).
The fact is that there are several methods to make opals quickly.
From a scientific point of view, these processes show that the right condition
are much more important to opal formation than long periods of time.
Rapid Formation Of Opals: Scientific Methods And Evidence
Opal, a hydrated amorphous form of silica, is well known for
its “play-of-color,” which results from the orderly arrangement of microscopic
silica spheres. Traditionally in classrooms and scientific literature, opal
formation has been associated with long geological timescales (e.g., millions
of years).
However, modern laboratory experiments and observations disprove
that it requires long ages. Opal and opal-like materials can form
rapidly—within days, weeks, or months—under the right chemical and physical
conditions.
At the heart of rapid opal formation is a simple but
powerful principle: silica must first form uniform microscopic spheres, which
then self-organize into a repeating structure and finally solidify through
dehydration or cementation. When these steps occur efficiently, the process can
be fast.
Cram’s Method
Len Cram, an Australian researcher, is known for proposing a
rapid formation model for precious opal based on well-understood principles of
silica chemistry and colloidal physics. Rather than viewing opal as requiring
vast geological time, Cram followed biblical principles that the key processes
are controlled by chemical conditions such as silica concentration, pH, and
evaporation rates.
In his model, silica-rich alkaline water becomes
supersaturated due to changes like cooling or evaporation. This triggers rapid
precipitation of silica in the form of uniform microscopic spheres. These
spheres, typically in the size range necessary to produce optical effects, are
the fundamental building blocks of precious opal.
Once formed, the silica spheres naturally—by the laws of
basic physics and chemistry—organize themselves into an ordered, tightly packed
structure through self-assembly driven by electrostatic and capillary forces.
This arrangement is what causes the different colors seen in opal.
As water is removed through dehydration and evaporation, the
structure compacts and solidifies into stable opal. Cram argued that when these
conditions are met efficiently, the entire process can occur on timescales of
weeks to months. His work shows that opal formation is governed more by
kinetics of materials and environmental conditions than by long durations of
time, aligning closely with modern laboratory observations of rapid silica
sphere formation and assembly.
Cram isn’t the only one that has figured out how to make
opals quickly. Let’s evaluate other popular scientific methods for rapid opal
formation.
Popular Methods
Stöber Process
One of the most important laboratory methods is the Stöber
process, developed in 1968. In this method, silicon alkoxides such as
tetraethyl orthosilicate are hydrolyzed in an alcohol-water solution with
ammonia as a catalyst. This produces highly uniform silica spheres in a matter
of minutes to hours.
Once formed, these spheres naturally settle and self-assemble into ordered arrays over days to weeks. As the liquid evaporates and the structure compacts, the result is an artificial opal-like material. The speed of this process is due to rapid supersaturation and controlled nucleation, which ensures that particles form quickly and remain uniform in size. This is one of the methods used to make gemstones (synthetic opals) for jewelry—often called a Gibson or Kyocera opal.
Electrophoretic Deposition
Another fast method is electrophoretic deposition. In this
technique, silica nanoparticles suspended in a liquid are driven by an electric
field toward a surface, where they deposit and pack into an ordered structure.
This can occur in minutes to hours, with final drying and
stabilization completed within a day or two. This approach allows
precise control over the structure and is widely used in photonic crystal
fabrication.
Evaporative Sedimentation
Self-assembly through evaporation or sedimentation provides
another pathway. In this case, silica spheres suspended in a liquid gradually
organize themselves as the liquid evaporates and/or as gravity causes
them to settle. Capillary forces during drying pull the spheres into a tightly
packed arrangement. This process typically takes days to weeks
and closely mimics natural opal formation in silica-rich waters.
Hydrogel-Based Synthesis
Hydrogel-based synthesis shows how researchers can make
opals via rapid formation under low-temperature conditions. Silica-rich
solutions can quickly form gels, sometimes within hours or days.
As these gels age and lose water, they polymerize into solid opaline
material. This process is especially important because it mirrors conditions
found in natural environments such as soils and sedimentary rocks.
Biogenic Processes
Biogenic processes also provide evidence for rapid opal
formation. Microorganisms such as bacteria and diatoms can mediate silica
precipitation, using organic structures as templates. Observations of
fossilized microbes preserved in opal indicate that such formation can occur
within weeks to months. These biological systems accelerate nucleation
and provide surfaces that encourage rapid mineral growth—much like a catalyst!
Geological Analogs
In addition to laboratory methods, geological analogs show
that opal can form quickly under certain environmental conditions. Silica-rich
alkaline fluids, particularly at elevated pH, can become supersaturated through
evaporation or cooling. This leads to rapid nucleation of silica spheres,
followed by aggregation and deposition in pores or fractures. Under strong
chemical gradients, these processes can occur on timescales far shorter than
traditionally assumed. This is the method that Len Cram used and the process
only took days to weeks to complete.
Polymer Impregnation
Finally, commercial synthetic opal production often uses
polymer impregnation techniques. After silica spheres are assembled into an
ordered structure, polymers or resins are introduced to stabilize the material.
These processes can be completed within days to weeks and are
commonly used to produce durable synthetic opals with strong visual effects.
Hence, this method is a common method used to make opals that are found in
gemstones for jewelry This and the Stöber process are used for jewelry.
Final Remarks
Across all these methods, three key factors consistently
enable rapid formation.
·
First, rapid supersaturation ensures that silica
precipitates quickly.
·
Second, the formation of uniform spheres allows
proper optical structure to develop.
·
Third, self-assembly combined with dehydration
locks the structure into place.
When these conditions are met, opal formation is governed
more by basic chemistry and kinetics than by long periods of time.
Both laboratory experiments and natural analogs show that
opal can form rapidly under the right conditions. While it is assumed, due to secular
humanistic worldview and timescale that it takes long ages to form opal, not
all natural opal deposits necessarily form quickly, the scientific evidence
clearly reveal that opal formation doesn’t inherently require long timescales.
Instead, it depends on the availability of silica, environmental conditions,
and the efficiency of nucleation and assembly processes.
These conditions were fully met in certain places and times during
the Flood of Noah’s day. I would suggest that hosts of catastrophic events since
the Flood could have rearrange natural silica and provided the conditions
needed to form opals. Though I would leave open the idea that some opals were
formed during the Creation Week (since other gemstones were made per Genesis
2), I would suggest that most opals were formed since that time.
Further Research:
- Stöber, W., Fink, A., & Bohn, E. (1968). Controlled growth of monodisperse silica spheres in the micron size range. Journal of Colloid and Interface Science.
- Norris, D. J., et al. (2003). Self-assembly of colloidal crystals for photonic applications. Advanced Materials.
- “Rapid fabrication of opal photonic crystals by electrophoretic deposition.” ACS Applied Optical Materials.
- “Origin of precious opal revisited: Possible quick formation of precious opal.” ResearchGate publication.
- Experimental silica gel and opal formation studies. Minerals (MDPI journal).
- Photonic crystal structure and silica sphere ordering. National Institutes of Health (PMC article).
- CSIRO and Gilson synthetic opal manufacturing methods. Opal Academy technical summaries.
- Growing Opals Australian Style, A.A. Snelling, Creation 12(1), December 1989, pp. 10-15.
- Microbial mediation of silica precipitation and rapid opal formation. Institute for Creation Research article discussing fossilized microbes in opal.
Bodie
Hodge, Ken Ham's son in law, has been an apologist defending 6-day creation and
opposing evolution since 1998. He spent 21 years working at Answers in
Genesis as a speaker, writer, and researcher as well as a founding
news anchor for Answers News. He was also head of the Oversight
Council.
Bodie
launched Biblical Authority Ministries in 2015 as a personal
website and it was organized officially in 2025 as a 501(c)(3). He has spoken
on multiple continents and hosts of US states in churches, colleges, and
universities. He is married with four children.
Mr.
Hodge earned a Bachelor and Master of Science degrees from Southern Illinois
University at Carbondale (SIUC). Then he taught at SIUC for a couple of
years as a Visiting Instructor teaching all levels of undergraduate engineering
and running a materials lab and a CAD lab. He did research on advanced ceramic
materials to develop a new method of production of titanium diboride with a
grant from Lockheed Martin. He worked as a Test Engineer for Caterpillar,
Inc., prior to entering full-time ministry.
His
love of science was coupled with a love of history, philosophy, and theology.
For about one year of his life, Bodie was editing and updating a theological,
historical, and scientific dictionary/encyclopedia for AI use and training. Mr.
Hodge has over 25 years of experience in writing, speaking and researching in
these fields.
[1]
The Fossil Cartel, How are opals formed, and what makes them so shiny?, Portland
Oregon, March 22, 2026, https://fossilcartel.com/how-are-opals-formed-and-what-makes-them-so-shiny/.
