CryptoCoins.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Text;
using System.Threading.Tasks;
using CryptoCoins;
using CryptoMarkets;

namespace CryptoMarkets
{
    class Program
    {
        private static async Task<string> GetCoins()
            => await new WebClient().DownloadStringTaskAsync(new Uri("https://api.coinmarketcap.com/v1/ticker/"));

        static void Main(string[] args)
        {
            var coins = Coins.FromJson(GetCoins().Result);
        }
    }
}

namespace CryptoCoins
{
    using System;
    using System.Collections.Generic;
    using System.Net;

    using System.Globalization;
    using Newtonsoft.Json;
    using Newtonsoft.Json.Converters;

    public class Coins
    {
        public static List<Dictionary<string, string>> FromJson(string json)
            => JsonConvert.DeserializeObject<List<Dictionary<string, string>>>(json, CryptoCoins.Converter.Settings);
    }

    public static class Serialize
    {
        public static string ToJson(this List<Dictionary<string, string>> self)
            => JsonConvert.SerializeObject(self, CryptoCoins.Converter.Settings);
    }

    internal class Converter
    {
        public static readonly JsonSerializerSettings Settings = new JsonSerializerSettings
        {
            MetadataPropertyHandling = MetadataPropertyHandling.Ignore,
            DateParseHandling = DateParseHandling.None,
            Converters = {
                new IsoDateTimeConverter()
                {
                    DateTimeStyles = DateTimeStyles.AssumeUniversal,
                },
            },
        };
    }
}