--- title: "Platinum Curidas: Retractable Nib, Sizes & Colors" canonical: "https://stationerytimes.com/guides/platinum-curidas/" description: "Platinum Curidas explained: a 153 mm, 24 g clear-resin knock fountain pen with a steel EF, F or M nib, its five colors, cartridges and converters." category: "Pens" type: "Fountain pen" published: 2026-10-23 updated: 2026-10-24 author: "Ellis Penhale" publisher: "Stationery Times" sources: 8 products: - name: "Platinum Curidas retractable fountain pen (PKN-7000), #50 Abyss Blue, Fine nib" brand: "Platinum" brand_origin: "Japan" made_in: "Not stated" material: "PMMA resin body, front barrel, knock bar and taper; chrome-plated brass inner thread; chrome-plated spring-steel clip; stainless steel nib (Platinum)" released: "2020-03-20" price_band: "$$$ ($20–75 per pen (multi-packs divided by the count), typical US retail, October 2026)" manufacturer: "Platinum Pen Co., Ltd. (Tokyo)" model: "PKN-7000 #50 Abyss Blue, F" sku: "1738502" gtin: "4977114113727" url: "https://www.platinum-pen.co.jp/products/fountain-pen/7848/" --- # Platinum Curidas: Retractable Nib, Sizes & Colors > The Platinum Curidas (PKN-7000) is a Japanese retractable fountain pen: press the knock bar and a steel nib slides out, with no cap to remove. Platinum lists it at 153 mm long, 13.8 mm across and 24.0 g, in five translucent colors with EF, F or M nibs. It sits in our $$$ band. - URL: https://stationerytimes.com/guides/platinum-curidas/ - Category: Pens - Author: Ellis Penhale - Published: 2026-10-23 - Updated: 2026-10-24 ![Platinum Curidas retractable fountain pen in Abyss Blue drawn to scale at 153 mm, with a close-up of the steel nib](https://stationerytimes.com/images/raster/platinum-curidas-16x9.png) *The Curidas in Abyss Blue, 153 mm with the nib retracted.* Original drawing (SVG): . Drawings © 2026 Stationery Times, reusable with credit under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). ## Product facts | Product | Brand | Brand origin | Made in | Material | Released | Price range (typical US retail, October 2026) | |---|---|---|---|---|---|---| | Platinum Curidas retractable fountain pen (PKN-7000), #50 Abyss Blue, Fine nib | Platinum (by Platinum Pen Co., Ltd. (Tokyo)) | Japan | Not stated | PMMA resin body, front barrel, knock bar and taper; chrome-plated brass inner thread; chrome-plated spring-steel clip; stainless steel nib (Platinum) | 2020-03-20 | $$$: $20–75 per pen (multi-packs divided by the count) | - Made in (Platinum Curidas retractable fountain pen (PKN-7000), #50 Abyss Blue, Fine nib): Not stated. Platinum's Japanese product page and launch release (read in full on October 23, 2026) don't state a country of manufacture, and the Amazon US listing we read doesn't either. Platinum is a Tokyo company; check the box. ### Platinum Curidas retractable fountain pen (PKN-7000), #50 Abyss Blue, Fine nib colors - Body colors (5 standard, 0 special edition): Prism Crystal; Graphite Smoke; Urban Green; Abyss Blue; Gran Red. - Ink in the box: Platinum blue-black cartridge (included). - Per Platinum Japan (https://www.platinum-pen.co.jp/products/fountain-pen/7848/), checked 2026-10-24. Five colors per Platinum Japan, which says a blue-black cartridge is included. Tints were sampled from the lineup image on Platinum's Curidas page; the cartridge tint from Platinum's photo of its blue-black SPN-100A cartridges. Shops stock different colors; check the listing. ## Key takeaways - Platinum Japan lists the Curidas at 153 mm (6.0 in) long, 13.8 mm at its widest and 24.0 g. - It went on sale in Japan on March 20, 2020, Platinum's first knock-type fountain pen in 55 years. - Platinum's Japanese list price is ¥7,700 (about US$49) including tax, for any of its five colors. - The body, front barrel and knock bar are PMMA resin; the clip is chrome-plated spring steel and comes off with the included tool. - Abyss Blue Fine had 354 Amazon US ratings on October 23, 2026, averaging 3.9 stars. ## What is the Platinum Curidas? **It's Platinum's capless, push-button fountain pen: one press of the knock bar slides the nib out, another pulls it back in.** Platinum named it from the knock mechanism and "curiosity", and pitches it at people who take notes on the move with one hand busy. Platinum's launch release says the Curidas went on sale on March 20, 2020, the company's first knock-type fountain pen in 55 years. Its first, the Platinum Knock, came out in 1965. It is one of the cheapest retractable fountain pens from a major Japanese maker. The Abyss Blue Fine listing on Amazon US had 354 ratings when we checked on October 23, 2026. ## Platinum Curidas specs | Spec | Platinum Curidas PKN-7000 | |---|---| | Length | 153 mm (6.0 in), nib retracted | | Maximum diameter | 13.8 mm (0.54 in) | | Weight | 24.0 g | | Body | PMMA resin; chrome-plated brass inner thread | | Clip | Chrome-plated spring steel, removable | | Nib | Stainless steel, EF, F or M | | In the box | One Blue-Black cartridge, clip tool | | Japan list price | ¥7,700 (about US$49) including tax | All figures come from Platinum's Japanese product page and launch release. At 153 mm it is longer than most capped pocket pens, so it suits a shirt pocket or a pen loop better than a small pouch. ## What colors does the Curidas come in? **Platinum Japan lists five translucent colors: #6 Prism Crystal, #7 Graphite Smoke, #43 Urban Green, #50 Abyss Blue and #77 Gran Red.** Each comes with EF, F or M, so there are 15 item codes; Abyss Blue Fine is 1738502, JAN 4977114113727. ![The five Platinum Curidas colors drawn to scale: Prism Crystal, Graphite Smoke, Urban Green, Abyss Blue and Gran Red, each 153 mm long, 13.8 mm wide and 24.0 g](https://stationerytimes.com/images/platinum-curidas-colors.svg) *The five regular colors, all the same size, drawn to one scale.* The clear resin shows the knock mechanism, which Platinum treats as part of the design. Platinum has also sold limited colors, including gem-themed ones in 2025 for the 60th anniversary of its first knock pen. ## How does the Curidas keep its nib from drying out? **A shutter closes the nib opening whenever the nib is retracted.** Platinum's Japanese Curidas page adds that the nib chamber is lined with a soft material for a tighter seal and kept small, so less moisture can escape. That matters because retractable pens can't use a screw cap's seal. Platinum is known for its "Slip & Seal" caps on pens such as the [Platinum Preppy](https://stationerytimes.com/guides/platinum-preppy/), and the Curidas applies the same goal to a capless design. ## What ink does the Platinum Curidas use? **It takes Platinum's proprietary cartridges, and one Blue-Black cartridge comes in the box.** For bottled ink, Platinum's Japanese product page lists its Converter 700A and 800A, according to search results we saw. Standard international cartridges don't fit Platinum pens. Our [converters guide](https://stationerytimes.com/guides/fountain-pen-converters-explained/) covers how the Platinum system compares with Pilot's and the international standard. ## How does the Curidas compare to the Pilot Vanishing Point? **The Curidas is longer, lighter and much cheaper, with a steel nib instead of gold.** The [Pilot Vanishing Point](https://stationerytimes.com/guides/pilot-vanishing-point/) is 140 mm and about 30 g per Goulet Pens, with an 18k gold nib and a metal body. | | Platinum Curidas | Pilot Vanishing Point | Majohn A1 | |---|---|---|---| | Length | 153 mm (6.0 in) | 140 mm (5.5 in) | About 138 mm (5.4 in) | | Weight | 24.0 g | About 30 g | About 30 g | | Nib | Steel, EF–M | 18k gold | Steel, EF | | Body | Resin | Metal | Metal | | Price band | $$$ | $$$$ | $$$ | The Chinese [Majohn A1](https://stationerytimes.com/guides/majohn-a1/) is the other budget option; it copies the Vanishing Point's layout, with the clip at the nib end. The Curidas' clip sits toward the back instead. ## What is the Curidas Depth? **A newer line that Platinum launched in Japan on May 1, 2023, as PKN-9000.** Platinum lists it at ¥9,900 (about US$63), the same 153 mm by 13.8 mm, and 24.1 g. Platinum briefly paused Curidas production in 2020 because of the pandemic, planning to restart in mid-November that year. The original PKN-7000 is still listed on Platinum's Japanese site. ## Where is the Platinum Curidas made? **Platinum doesn't say on its product pages.** Platinum Pen Co., Ltd. is based in Tokyo, but neither its Japanese pages nor the Amazon US listing we read gives a country of manufacture. For Platinum's history from 1919 to today, see our [Platinum company story](https://stationerytimes.com/stories/platinum-pen-history/). ## Frequently asked questions ### Does the Platinum Curidas dry out? Platinum designed against it: a shutter closes over the nib opening when you retract it, and a soft seal and a small air space around the nib limit evaporation, according to Platinum's Japanese Curidas page. We haven't tested how long it sits unused before skipping. ### What cartridges does the Curidas take? Platinum's own proprietary cartridges; one Blue-Black cartridge comes in the box. Platinum's Japanese product page also lists its Converter 700A and 800A for bottled ink, according to search results we saw. ### Can you remove the clip on the Curidas? Yes. Platinum includes a small clip tool for taking the chrome-plated clip off and putting it back, so you can use the pen clipless. ### Is the Curidas cheaper than a Pilot Vanishing Point? Yes, by a wide margin. The Curidas has a steel nib and a resin body in our $$$ band ($20–75), while the Vanishing Point has an 18k gold nib and a metal body. ### When did the Platinum Curidas Depth come out? A later version, PKN-9000, released in Japan on May 1, 2023 at ¥9,900 (about US$63). Platinum lists it at the same 153 mm and 13.8 mm, and 24.1 g. ### What nib sizes does the Curidas come in? EF (extra fine), F (fine) and M (medium), all stainless steel. Platinum's Japanese EF and F run finer than European sizes, so the EF suits small handwriting in planners. ## Sources - [Platinum Pen (Japanese): キュリダス PKN-7000 product page (stainless nib EF/F/M, PMMA body, 153 mm, 13.8 mm, 24.0 g, ¥7,700, five colors and item codes; read October 23, 2026)](https://www.platinum-pen.co.jp/products/fountain-pen/7848/) - [Platinum Pen (Japanese): 片手でノックして、すぐに筆記できる ノック式万年筆「キュリダス」登場 (launch release, February 17, 2020: on sale March 20, 2020, materials, clip tool)](https://www.platinum-pen.co.jp/news/8910/) - [Platinum Pen (Japanese): curidas brand page (shutter and seal design, removable clip, 1965 Platinum Knock, JAN codes for all 15 color and nib combinations)](https://www.platinum-pen.co.jp/curidas_jp.html) - [Platinum Pen (Japanese): キュリダス（PKN-7000）一時生産中止のお知らせ (2020 production pause, restart planned mid-November 2020)](https://www.platinum-pen.co.jp/news/9553/) - [Platinum Pen (Japanese): キュリダス デプス PKN-9000 (May 1, 2023, ¥9,900, 24.1 g)](https://www.platinum-pen.co.jp/news/11723/) - [Platinum Pen (Japanese): 60th-anniversary limited Curidas (July 25, 2025)](https://www.platinum-pen.co.jp/news/13030/) - [Amazon US: Platinum Fountain Pen, Curidas, Abyss Blue, Fine Point, PKN-7000#50-2 (354 ratings, 3.9 stars, October 23, 2026)](https://www.amazon.com/dp/B084441DS2) - [Platinum Japan: cartridge ink SPN-100A (blue-black cartridge photo)](https://www.platinum-pen.co.jp/products/ink/2872/)