Not every pocket knife has to be a 3.5-inch workhorse. The CJRB Mica J1934 is the other answer: a 2.36-inch AR-RPM9 blade on a 53 g frame with a button lock, five and a half inches open, and a handle that changes character completely depending on which tier you buy. It exists in three published handle materials — aluminum, Ultem, and forged carbon — at three very different prices. This guide walks through the CJRB Mica's specifications tier by tier, separates what is in stock from what is not, and compares it against the other sub-2.6-inch button locks CJRB builds.
The J1934 is offered in aluminum, forged carbon, and Ultem handle tiers at three price points.
CJRB Mica J1934: Published Specifications
The figures below are the published specifications for the aluminum-handled J1934, currently the tier with stock available.
| Specification | CJRB Mica J1934 |
|---|---|
| Model code | J1934 |
| Blade length | 2.36 in (60 mm) |
| Blade thickness | 0.09 in (2.3 mm) |
| Blade style | Drop point |
| Blade grind | Flat |
| Blade steel | AR-RPM9, HRC 59-61 |
| Blade finish | Sand polish or black PVD coating, by colourway |
| Handle material | Aluminum |
| Lock type | Button lock |
| Pivot assembly | Ceramic ball bearing |
| Overall length | 5.57 in (141.5 mm) |
| Closed length | 3.21 in (81.5 mm) |
| Weight | 53 g / 1.87 oz |
| Clip | Steel |
| Price range | $36.79 to $45.99 |
Fifty-three grams is the number to hold onto. For reference, most of the CJRB crossbar line sits between 76 g and 100 g. The Mica is roughly two-thirds the weight of the Shale J1943 and less than half the weight of the Bellona J1947, which matters if the knife rides in a shirt pocket, a waistband, or lightweight running shorts.
Three Handle Tiers, Three Prices, Three Characters
This is the part of the Mica story that a spec sheet hides. The same model code appears at three price points, and the difference is the handle material and how it is finished.
| Tier | Handle | SKU | Price | Availability |
|---|---|---|---|---|
| Aluminum | Sand polish / black PVD aluminum | J1934-BK, PK, BU, GN, BBK, BPK | $36.79 - $45.99 | 4 of 6 colourways in stock |
| Forged carbon | Forged carbon | J1934-FCBK, FCBU, FCRE | $44.79 - $55.99 | Sold out |
| Ultem | Ultem (amber) | J1934-AMB | $74.65 | Sold out |
Aluminum is the value tier and the one to buy today. Aluminum handles are stiff and light, and they accept a sand-blasted matte finish — sandblasting is the abrasive process that produces that fine, even, non-reflective surface — or a black PVD coating on top. It is also the most repairable and the least precious: a scuffed aluminum scale is a cosmetic event, not a tragedy.
Forged carbon is the mid tier at $44.79 to $55.99. Forged carbon is a compression-moulded chopped-carbon-fibre composite, in the same broad material family as the carbon-fibre-reinforced polymers used across high-end gear. It gives a marbled, non-directional pattern rather than the regular weave of sheet carbon fibre, and it is lighter and stiffer than the aluminum tier. This tier is sold out at the time of writing.
Ultem is the top tier at $74.65 — a translucent amber material, the same polyetherimide described on the Ultem page, used in aerospace and medical components for its stiffness, heat resistance, and dimensional stability. On a knife it reads as a warm honey-amber handle that shows the internal structure beneath the surface. It is also the heaviest-priced and the hardest to restock, and it is sold out.
One data note worth flagging before you order: the forged-carbon listing publishes a 2.17 in (55 mm) blade and a 5.32 in (135 mm) overall length, while the aluminum and Ultem listings publish 2.36 in (60 mm) and 5.57 in (141.5 mm) for the same J1934 model code. Both sets of figures are internally consistent — each adds up to its own overall length — but they do not agree with each other. If exact blade length matters to you, confirm the figure for the specific tier you are buying.
How a Button Lock Behaves on a 53 g Knife
The Mica uses a button lock: a spring-loaded plunger in the handle that engages the blade tang, released by pressing the button on the presentation side. Press it and the blade swings on ceramic ball bearings; the published spec lists a ceramic bearing pivot, the same assembly used across this CJRB generation.
On a small, light knife the button lock has a specific advantage over a liner lock: it does not depend on a leaf spring in a thin handle slab. On a 53 g frame there is simply less material to house a liner, and the geometry of a transverse button is a tidier fit. The practical payoff is a fidget-friendly, one-handed open and close that does not require repositioning your grip between the two.
The usual caveats apply and are worth knowing. A button lock is not a fixed blade — a knife this light should be treated as a light-duty cutting tool, not a pry bar. And like any open bearing pivot, it benefits from an occasional flush and a drop of oil rather than a lifetime of neglect.
CJRB Mica vs the Other Small CJRB Button Locks
If you are shopping the smallest end of the CJRB line-up, three other models belong in the comparison. All figures are published listing specifications with current in-stock pricing.
| Model | Blade length | Blade steel | Handle | Weight | Price |
|---|---|---|---|---|---|
| Mica J1934 | 2.36 in (60 mm) | AR-RPM9 | Aluminum | 53 g | $36.79 - $45.99 |
| Version J1949 | 2.6 in (65 mm) | AR-RPM9 | Aluminum and G10 | 48 g | $49.99 |
| Mini Pyrite J1933 | 2.17 in (55 mm) | CPM S90V, HRC 60-62 | Fat Carbon | 48.6 g | $189.00 |
| Boxer J1967 | 2.3 in (58.5 mm) | Replaceable utility blade | G10 | 61 g | $34.99 |
The four knives are not competitors so much as four different jobs. The Version J1949 is the direct alternative: 5 mm more blade, a two-material aluminum-and-G10 handle, 48 g, and it is the lightest of the group in the hand. The Mini Pyrite J1933 is a different class of object entirely — a limited edition running CPM S90V at HRC 60-62 on a Fat Carbon handle, at roughly four times the Mica's price. The Boxer J1967 is a folding utility knife that ships with ten spare blades, which makes it the right pick for anyone whose knife mostly opens cartons.
Where the Mica wins is the combination of price and mass: it is the cheapest way into a genuine button-lock CJRB with a proper blade steel, and it is the middle of the group on weight while being the widest available in colour. Four of its six aluminum colourways are in stock at the time of writing, from $36.79 to $45.99.
Carry Notes for a 53 g Knife
- Pocket placement matters more than usual. At 53 g with an 81.5 mm closed length, the Mica is short enough to sit unnoticed in a coin pocket or a shirt pocket, where a heavier folder would sag.
- Check your local blade-length limits. A 2.36 in blade falls inside the common 2.5 in and 3 in statutory thresholds in many jurisdictions, but laws vary and this guide is not legal advice.
- Match the finish to the use. Sand polish shows handling marks sooner; black PVD hides them. Neither affects the edge.
- Keep expectations calibrated. A 2.36 in blade in 0.09 in stock is a precise slicer, not a demolition tool.
Frequently Asked Questions
How much does the CJRB Mica weigh?
53 g / 1.87 oz according to the published specification, across the aluminum, Ultem, and forged-carbon listings.
Is the CJRB Mica a button lock?
Yes. The published lock type is a button lock, engaged by a plunger in the handle and released by pressing the button.
What steel does the Mica J1934 use?
AR-RPM9 at a published hardness of HRC 59-61 in all three tiers. The limited-edition Mini Pyrite J1933 is the model that steps up to CPM S90V.
Why is the Ultem Mica so much more expensive?
Material cost. Ultem is a high-performance polyetherimide with aerospace and medical applications, priced well above aluminum and forged carbon, and the tier is currently sold out.
Is the Mica J1934 a good first EDC knife?
It is a reasonable second or third knife and an excellent small-knife specialist. For a first knife, the larger Shale J1943 or Lyrid J1953 at the same price band gives you more blade to learn with.
See every current configuration on the CJRB Mica collection page, or browse the full CJRB button lock collection for the rest of the plunger-lock line-up. Model codes, steels, and handle materials for the whole catalogue are on the CJRB all-model index.
Leave a comment
This site is protected by hCaptcha and the hCaptcha Privacy Policy and Terms of Service apply.